Re: Ultra-wide zooms
Hi there, I have tested DA15 Limited vs DA14 some time ago (wrote a review). Many have said that DA14 is better simply because it is a stop faster. Me personally, I would avoid it at f/2.8 unless absolutely necessary. Test it as much as you like - it's still soft and vignetting full open. At f/4 it's much better and outperforms DA15 Limited a bit. At f/5.6 there was no difference between 'em. Is it worth to have a MUCH larger and heavier lens, that performs quite sluggish full-open? One more thing - I never use DA14 without a hood. Never, even indoors. DA15 Limited also needs protection from side-light, but at least the hood is built-in. The conclusion? If I wouldn't already own the DA14, I'd go for DA15 Limited. BR, Margus Adam Maas wrote: All the reviews I've read indicate a slight decrease in performance for the 15/4 over the 14/2.8 at the edge, which is consistent with the design differences. While the 15 is slower, it's also a far less complex (8/6) design than the 14 is (12/11) so it will remain less well corrected. The differences in focal length is very minor and won't have a serious impact on the design complexity. -Adam On Thu, Apr 15, 2010 at 11:31 PM, J.C. O'Connell wrote: I read a review on the da15 and they said it outperformed the earlier da14 lens, which wouldn’t surprise me, its not as wide and slower than the da14. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam Maas Sent: Thursday, April 15, 2010 9:12 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms New design, optimized for size over performance. Quite a good lens, but inferior in performance to both the DA 14/2.8 and DA 12-24/4. Smaller than a FA 50/1.4 though. Like the DA 21/3.2 it's marginally inferior to the older and larger equivalent design. -Adam On Thu, Apr 15, 2010 at 8:51 PM, J.C. O'Connell wrote: what about the DA 15mm? -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of P. J. Alling Sent: Thursday, April 15, 2010 7:32 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms Unfortunatly it hasn't been done. Most prime designs are at least 10 years old. In the case of the DA 40mm limited it looks like it's about thirty years old, (see the M 40mm f2.8). On 4/15/2010 1:35 PM, J.C. O'Connell wrote: How many times do I have to tell you to make the point? A zoom has to do much more than a prime so the zoom cannot be "better" or even equal to a prime with BOTH using state of the art designs and optics, period. Whatever they do to improve zoom performance over the years can also be applied to primes. the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms [Scanned][Spam score:8%]
"As far as my very limited experience allows me to opine, people don't like primes because they don't like changing lenses." -- Graydon I love primes, but use a Sigma 10-20 f/4-5.6 for the wide end. I could have bought a DA 14 f/2.8 but I'd be limited to 14mm. Now if all the primes covered by the Sigma 10-20mm were available, which they're not I still wouldn't buy them because I couldn't fir them in the kit bag! My standard kit consists of the following: Sigma EX 10-20 OR Pentax DA*16-50 Sigma AF 24/2.8 Pentax FA 28/2.8 Pentax FA 35/2 Pentax FA 50/1.4 Pentax DA 70/2.4 Limited Tamron Di 90/2.8 Macro Pentax FA 135/2.8 The DA 14/2.8 is roughly the size of the Sigma 10-20 and offers very little in th way of extra IQ, it gains a faster aperture but looses flexibility in spades. But I have to agrree with JC on this, a modern prime will beat a modern zoom every time if made to the same standard. I have the DA*200/2.8 and DA 300/4 and they're just awesome!!! John -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On 4/17/2010 9:59 AM, Graydon wrote:
On Thu, Apr 15, 2010 at 07:32:26PM -0400, P. J. Alling scripsit:
Unfortunatly it hasn't been done. Most prime designs are at least 10
years old. In the case of the DA 40mm limited it looks like it's about
thirty years old, (see the M 40mm f2.8).
[256 lines snipped]
DA 35 Ltd. would appear to be a new design and both a very capable one
and one that is, in the context of "Limited" branded lenses, affordable.
As far as my very limited experience allows me to opine, people don't
like primes because they don't like changing lenses.
-- Graydon
I did say /most/ some designs are brand new, and Pentax has a lot of them.
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Re: Ultra-wide zooms
On Thu, Apr 15, 2010 at 07:32:26PM -0400, P. J. Alling scripsit: > Unfortunatly it hasn't been done. Most prime designs are at least 10 > years old. In the case of the DA 40mm limited it looks like it's about > thirty years old, (see the M 40mm f2.8). [256 lines snipped] DA 35 Ltd. would appear to be a new design and both a very capable one and one that is, in the context of "Limited" branded lenses, affordable. As far as my very limited experience allows me to opine, people don't like primes because they don't like changing lenses. -- Graydon -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
All the reviews I've read indicate a slight decrease in performance for the 15/4 over the 14/2.8 at the edge, which is consistent with the design differences. While the 15 is slower, it's also a far less complex (8/6) design than the 14 is (12/11) so it will remain less well corrected. The differences in focal length is very minor and won't have a serious impact on the design complexity. -Adam On Thu, Apr 15, 2010 at 11:31 PM, J.C. O'Connell wrote: > I read a review on the da15 and they said it outperformed > the earlier da14 lens, which wouldn’t surprise me, its > not as wide and slower than the da14. > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam > Maas > Sent: Thursday, April 15, 2010 9:12 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > New design, optimized for size over performance. Quite a good lens, but > inferior in performance to both the DA 14/2.8 and DA 12-24/4. Smaller than a > FA 50/1.4 though. Like the DA 21/3.2 it's marginally inferior to the older > and larger equivalent design. > > -Adam > > On Thu, Apr 15, 2010 at 8:51 PM, J.C. O'Connell wrote: >> what about the DA 15mm? >> >> -- >> J.C. O'Connell (mailto:hifis...@gate.net) >> Join the CD PLAYER & DISC Discussions : >> http://tech.groups.yahoo.com/group/cdplayers/ >> http://launch.groups.yahoo.com/group/cdsound/ >> >> >> -Original Message----- >> From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf >> Of P. J. Alling >> Sent: Thursday, April 15, 2010 7:32 PM >> To: Pentax-Discuss Mail List >> Subject: Re: Ultra-wide zooms >> >> >> Unfortunatly it hasn't been done. Most prime designs are at least 10 >> years old. In the case of the DA 40mm limited it looks like it's about >> thirty years old, (see the M 40mm f2.8). >> >> On 4/15/2010 1:35 PM, J.C. O'Connell wrote: >>> How many times do I have to tell you to make the point? >>> A zoom has to do much more than a prime so the zoom cannot be >>> "better" or even equal to a prime with BOTH using state of the art >>> designs and optics, period. Whatever they do to improve zoom >>> performance over the years can also be applied to primes. >> the PDML, please visit the link directly above and follow the >> directions. >> >> >> -- >> PDML Pentax-Discuss Mail List >> PDML@pdml.net >> http://pdml.net/mailman/listinfo/pdml_pdml.net >> to UNSUBSCRIBE from the PDML, please visit the link directly above and >> follow the directions. >> > > > > -- > M. Adam Maas > http://www.mawz.ca > Explorations of the City Around Us. > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
I read a review on the da15 and they said it outperformed the earlier da14 lens, which wouldnt surprise me, its not as wide and slower than the da14. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam Maas Sent: Thursday, April 15, 2010 9:12 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms New design, optimized for size over performance. Quite a good lens, but inferior in performance to both the DA 14/2.8 and DA 12-24/4. Smaller than a FA 50/1.4 though. Like the DA 21/3.2 it's marginally inferior to the older and larger equivalent design. -Adam On Thu, Apr 15, 2010 at 8:51 PM, J.C. O'Connell wrote: > what about the DA 15mm? > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf > Of P. J. Alling > Sent: Thursday, April 15, 2010 7:32 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > Unfortunatly it hasn't been done. Most prime designs are at least 10 > years old. In the case of the DA 40mm limited it looks like it's about > thirty years old, (see the M 40mm f2.8). > > On 4/15/2010 1:35 PM, J.C. O'Connell wrote: >> How many times do I have to tell you to make the point? >> A zoom has to do much more than a prime so the zoom cannot be >> "better" or even equal to a prime with BOTH using state of the art >> designs and optics, period. Whatever they do to improve zoom >> performance over the years can also be applied to primes. > the PDML, please visit the link directly above and follow the > directions. > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
John Sessoms wrote: From: Keith Whaley [...] How the H*** can anyone BUY one if nobody will MAKE one? That?s a real head-shaker... I think you might not have picked up on just a touch of irony. Happens from time to time... keith -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Charles Robinson wrote: On Apr 15, 2010, at 15:40, Keith Whaley wrote: [...] How the H*** can anyone BUY one if nobody will MAKE one? That�s a real head-shaker... Keith - Perhaps you didn't read the same tone of irony in Larry's post that I did. -Charles Perhaps. keith -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
New design, optimized for size over performance. Quite a good lens, but inferior in performance to both the DA 14/2.8 and DA 12-24/4. Smaller than a FA 50/1.4 though. Like the DA 21/3.2 it's marginally inferior to the older and larger equivalent design. -Adam On Thu, Apr 15, 2010 at 8:51 PM, J.C. O'Connell wrote: > what about the DA 15mm? > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of P. > J. Alling > Sent: Thursday, April 15, 2010 7:32 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > Unfortunatly it hasn't been done. Most prime designs are at least 10 > years old. In the case of the DA 40mm limited it looks like it's about > thirty years old, (see the M 40mm f2.8). > > On 4/15/2010 1:35 PM, J.C. O'Connell wrote: >> How many times do I have to tell you to make the point? >> A zoom has to do much more than a prime so the zoom cannot >> be "better" or even equal to a prime with BOTH using state of the art >> designs and optics, period. Whatever they do to improve zoom >> performance over the years can also be applied to primes. > the PDML, please visit the link directly above and follow the directions. > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
what about the DA 15mm? -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of P. J. Alling Sent: Thursday, April 15, 2010 7:32 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms Unfortunatly it hasn't been done. Most prime designs are at least 10 years old. In the case of the DA 40mm limited it looks like it's about thirty years old, (see the M 40mm f2.8). On 4/15/2010 1:35 PM, J.C. O'Connell wrote: > How many times do I have to tell you to make the point? > A zoom has to do much more than a prime so the zoom cannot > be "better" or even equal to a prime with BOTH using state of the art > designs and optics, period. Whatever they do to improve zoom > performance over the years can also be applied to primes. the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
From: Keith Whaley Larry Colen wrote: > On 4/15/2010 11:23 AM, CheekyGeek wrote: >> On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: >> >>> The analysis of "would people rather buy three primes to cover the >>> range of 10-20mm or one zoom?" seems to always come up with the >>> answer "one zoom". >> Can somebody point me to this 10mm rectilinear prime that would cover >> the wide end of this 10-20mm range? > There isn't a market for one, if there were they'd make it. > > They know that there isn't a market for one, because nobody buys any. -= WHAT =- ? Their rationale for not MAKING one is that nobody buys any? Take off your tinfoil hat and say that again. How the H*** can anyone BUY one if nobody will MAKE one? That?s a real head-shaker... I think you might not have picked up on just a touch of irony. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On 4/15/2010 2:38 PM, Larry Colen wrote:
On 4/15/2010 11:23 AM, CheekyGeek wrote:
On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote:
The analysis of "would people rather buy three primes to cover the
range of
10-20mm or one zoom?" seems to always come up with the answer "one
zoom".
Can somebody point me to this 10mm rectilinear prime that would cover
the wide end of this 10-20mm range?
There isn't a market for one, if there were they'd make it.
They know that there isn't a market for one, because nobody buys any.
Nobody goes there anymore it's too crowded. Wait. What?
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Re: Ultra-wide zooms
Unfortunatly it hasn't been done. Most prime designs are at least 10 years old. In the case of the DA 40mm limited it looks like it's about thirty years old, (see the M 40mm f2.8). On 4/15/2010 1:35 PM, J.C. O'Connell wrote: How many times do I have to tell you to make the point? A zoom has to do much more than a prime so the zoom cannot be "better" or even equal to a prime with BOTH using state of the art designs and optics, period. Whatever they do to improve zoom performance over the years can also be applied to primes. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER& DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam Maas Sent: Thursday, April 15, 2010 11:12 AM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms You're clearly not up on the latest developments in lens design. Comparing the best UW prime on the market (The Zeiss 21mm f2.8 Distagon T* in ZK, ZE or ZF mounts) and the best UW zoom on the market, the Nikkor 14-24mm f2.8 G, the zoom has less elements (14 elements in 11 groups for the Nikkor, 16 elements in 13 groups for the Zeiss), although the zoom makes heavy use of exotic glass to achieve this (2 ED elements, 3 aspherical elements, 1 nano-crystal coated element, the latter is unique to Nikon and seriously reduces flare). The Zeiss 21 actually does outperform the Nikkor at 21mm, but only by a small amount (and the zoom has superior flare performance despite its massive front element) and the Zeiss outperforms similar primes by a much larger margin than it does the zoom. Note that the Zeiss 21 is one of the very few truly modern wide prime designs (a 2009 update of a design from 1994), aside from the Pentax DA's, the only other new wide primes are the current set of 14's (Canon's 14LII, the Nikkor 14/2.8D which is the oldest at ~2001 and the brand new Samyang 14/2.8) and Sigma's massive f1.8's (which are good, fast but not exceptional). Simply put, modern molded aspherics, use of low-dispersion elements and other radical tech like Nikon's Nano-crystal coating has functionally removed the advantages of prime designs for wide-angle lenses unless you are trying to make a lens faster than f2.8. The requirements of a retrofocus design simply grow to a point where the requirements for a zoom are irrelevant to anything except size. Making a world class UW requires a very high element count, prime or zoom. Modern digital cameras are simply too demanding for edge performance, particularly high-MP FF cameras. As to the DA 15/4 Limited, it's actually slightly inferior in performance to the DA 14/2.8, and the latter is pretty much identical in performance to the 12-24/4 aside from the extra stop (and the DA 14 is the best performing 14 on APS-C). -Adam On Thu, Apr 15, 2010 at 10:43 AM, J.C. O'Connell wrote: ultra wide primes require many more elements than primes do and the results is more flare they will never match a prime because even primes need too many elements for high performance flare performance. what is being sold doesn’t prove anything other than market demand. Prime can outdo zooms especially on ultrawides. what about the 15mm DA lens?? -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER& DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam Maas Sent: Wednesday, April 14, 2010 7:30 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms LOL, That may have been true 5 years ago, but it simply isn't now. Current state of the art in lenses wider than 21mm for SLR mounts are all zooms. There are no APS-C or 35mm format SLR primes which exceed the performance of zooms like the Nikkor 14-24/2.8, Zeiss ZA 16-35/2.8 or either of the 7-14/4'sfrom Oly/Panasonic at focal lengths wider than 21mm (And the only reason why 21mm matters is the Zeiss 21mm f2.8 Distagon. which simply dominates the UW prime world for performance). Current coating technology has greatly reduced the issue of increased element count (note the Zeiss 21 has an element count which is only slightly lower than the equivalent zooms) and the increased element count allows correction of distortion and removal of edge performance issues which plague even the best older UW primes. Most basic wide primes at best match the performance of today's high-end wide zooms, there have been very few new-design wide primes introduced in the last 20 years while zoom performance has increased massively and most zooms in this range are new designs form the last few years. The real downside for us is that none of the best zoom options are available
Re: Ultra-wide zooms
2010/4/15 Larry Colen : > On 4/15/2010 1:43 PM, Charles Robinson wrote: >> >> On Apr 15, 2010, at 15:40, Keith Whaley wrote: >> >>> Larry Colen wrote: On 4/15/2010 11:23 AM, CheekyGeek wrote: > > On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: > >> The analysis of "would people rather buy three primes to cover the >> range of 10-20mm or one zoom?" seems to always come up with the >> answer "one zoom". >>> > Can somebody point me to this 10mm rectilinear prime that would cover > the wide end of this 10-20mm range? >>> There isn't a market for one, if there were they'd make it. They know that there isn't a market for one, because nobody buys any. >>> >>> -= WHAT =- ? >>> >>> Their rationale for not MAKING one is that nobody buys any? >>> >>> Take off your tinfoil hat and say that again. >>> >>> How the H*** can anyone BUY one if nobody will MAKE one? >>> >>> That’s a real head-shaker... >>> >> >> Keith - >> >> Perhaps you didn't read the same tone of irony in Larry's post that I did. > > He definitely fell into the sarchasm. Hope he at least got a sargasm out of it -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On 4/15/2010 1:43 PM, Charles Robinson wrote: On Apr 15, 2010, at 15:40, Keith Whaley wrote: Larry Colen wrote: On 4/15/2010 11:23 AM, CheekyGeek wrote: On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: The analysis of "would people rather buy three primes to cover the range of 10-20mm or one zoom?" seems to always come up with the answer "one zoom". Can somebody point me to this 10mm rectilinear prime that would cover the wide end of this 10-20mm range? There isn't a market for one, if there were they'd make it. They know that there isn't a market for one, because nobody buys any. -= WHAT =- ? Their rationale for not MAKING one is that nobody buys any? Take off your tinfoil hat and say that again. How the H*** can anyone BUY one if nobody will MAKE one? That’s a real head-shaker... Keith - Perhaps you didn't read the same tone of irony in Larry's post that I did. He definitely fell into the sarchasm. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On Apr 15, 2010, at 15:40, Keith Whaley wrote: > Larry Colen wrote: >> On 4/15/2010 11:23 AM, CheekyGeek wrote: >>> On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: >>> The analysis of "would people rather buy three primes to cover the range of 10-20mm or one zoom?" seems to always come up with the answer "one zoom". > >>> Can somebody point me to this 10mm rectilinear prime that would cover >>> the wide end of this 10-20mm range? > >> There isn't a market for one, if there were they'd make it. >> They know that there isn't a market for one, because nobody buys any. > > -= WHAT =- ? > > Their rationale for not MAKING one is that nobody buys any? > > Take off your tinfoil hat and say that again. > > How the H*** can anyone BUY one if nobody will MAKE one? > > That’s a real head-shaker... > Keith - Perhaps you didn't read the same tone of irony in Larry's post that I did. -Charles -- Charles Robinson - charl...@visi.com Minneapolis, MN http://charles.robinsontwins.org http://www.facebook.com/charles.robinson -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Thanks for playing, Keith! We have some lovely parting gifts for you... :) -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Larry Colen wrote: On 4/15/2010 11:23 AM, CheekyGeek wrote: On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: The analysis of "would people rather buy three primes to cover the range of 10-20mm or one zoom?" seems to always come up with the answer "one zoom". Can somebody point me to this 10mm rectilinear prime that would cover the wide end of this 10-20mm range? There isn't a market for one, if there were they'd make it. They know that there isn't a market for one, because nobody buys any. -= WHAT =- ? Their rationale for not MAKING one is that nobody buys any? Take off your tinfoil hat and say that again. How the H*** can anyone BUY one if nobody will MAKE one? That’s a real head-shaker... keith whaley -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
From: CheekyGeek As an (important?) aside, I recently bought the Sigma 10-20mm f4-5.6 (used) and read that it WILL cover a full 35mm frame down to 13mm. I plan on trying this myself with my Z-1p. I'm sure the corners will suffer, but WOW... a 13mm rectilinear focal length with no field-of-view crop? If true, it is amazing that they don't promote this. Lesson: Don't ASSUME your lenses designed for APS-C won't cover the full 35mm. They just may not do it over the whole zoom range. Haven't USED it on the PZ-1p, but looking through the viewfinder ... At 10mm it's like lookin' through a porthole. At 12mm there's still a tiny bit of vignetting at the corners At 14mm - 20mm there's no visible vignetting, but there is a slight, but noticeable, light fall-off at the corners. The equivalence is more of a shorthand for photographers who were > accustomed to how 35mm focal lengths worked, and it has really > outlived it's utility. Well a focal length is a focal length is a focal length but if you are an old school 35mm film shooter then a particular lens focal length translates in your mind to a particular field-of-view. When you crop that you haven't changed the effect of the focal length (think: squashed depth with a particular telephoto focal length, for example) but you HAVE changed the field-of-view. For a radical example illustrating this principle, put a F 17-28mm fisheye zoom on a Pentax DSLR. You've still got the fisheye distortion you associate with ultrawide, but you are cropping the center out of the field-of-view (an effective 25-42mm with fisheye curves... which can be very interesting!) Bottom line, if you think in terms of field of view, AND you used to shoot film (or you STILL also shoot film), the equivalence continues to have more than a little utility. It is similar to an older American who will always need to convert metric units to imperial units in order to grasp what is being talked about. A younger generation that simply learned the metric system without having the base knowledge of imperial units would certainly not need that utility. Well, the way it's expressed - as an equivalent focal length - is wrong. It's not an equivalent focal length. Equivalent field of view or angle of view works, but it's still confusing. All I really care about is whether the image circle is large enough for the sensor, be it APS-C or "full frame". I would prefer lenses with an image circle large enough to cover the "full frame", although I have some lenses that won't and I still use them ... just not on the film cameras. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
Id bet that a good 10mm Prime DA Lens would be way too high a cost to produce, even if it did outperform the 10-20mm at 10mm. FWIW - Pentax DID eventually produce a 15mm for full frame 35mm film which would similar to the angle of 10mm on APS. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Larry Colen On 4/15/2010 11:23 AM, CheekyGeek wrote: > On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: > >> The analysis of "would people rather buy three primes to cover the >> range of 10-20mm or one zoom?" seems to always come up with the >> answer "one zoom". > > Can somebody point me to this 10mm rectilinear prime that would cover > the wide end of this 10-20mm range? There isn't a market for one, if there were they'd make it. They know that there isn't a market for one, because nobody buys any. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On 4/15/2010 11:23 AM, CheekyGeek wrote: On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: The analysis of "would people rather buy three primes to cover the range of 10-20mm or one zoom?" seems to always come up with the answer "one zoom". Can somebody point me to this 10mm rectilinear prime that would cover the wide end of this 10-20mm range? There isn't a market for one, if there were they'd make it. They know that there isn't a market for one, because nobody buys any. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On Thu, Apr 15, 2010 at 12:49 PM, Larry Colen wrote: > The analysis of "would people rather buy three primes to cover the range of > 10-20mm or one zoom?" seems to always come up with the answer "one zoom". Can somebody point me to this 10mm rectilinear prime that would cover the wide end of this 10-20mm range? Darren Addy Kearney, NE Fact: Pentax DSLRs attract more photographers with Asperger's Syndrome than any other brand! -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
What is marketable vs what is possible with primes are two different things. What I didn't agree with is the contention that SOTA zooms can match or beat SOTA primes in the ultra wide range of focal lengths. What is on the market is a different matter altogether but there is that 15mm DA lens, but I doubt its SOTA because of its low cost relatively speaking. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Larry Colen On 4/15/2010 10:35 AM, J.C. O'Connell wrote: > How many times do I have to tell you to make the point? > A zoom has to do much more than a prime so the zoom cannot > be "better" or even equal to a prime with BOTH using state of the art > designs and optics, period. Whatever they do to improve zoom > performance over the years can also be applied to primes. I think that you are confusing physics with market realities. I don't think that anyone is doubting that it would be possible to make a prime that outperforms any of the ultrawide zooms on the market. The reality is that (to a first approximation) nobody is doing so. The lens manufacturers seem to think that nobody is interested in prime lenses. How many image stabilized primes (under 400mm) are made these days? How many prime "kit lenses" are there? The analysis of "would people rather buy three primes to cover the range of 10-20mm or one zoom?" seems to always come up with the answer "one zoom". -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
2010/4/15 Larry Colen : > > The analysis of "would people rather buy three primes to cover the range of > 10-20mm or one zoom?" seems to always come up with the answer "one zoom". Which is market logic. Just compare the systems of old and the systems of now. Cheers Ecke -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On Thu, Apr 15, 2010 at 12:34:59PM -0400, John Francis wrote: > On Thu, Apr 15, 2010 at 10:58:23AM -0500, CheekyGeek wrote: > > > > Well a focal length is a focal length is a focal length but if you are > > an old school 35mm film shooter then a particular lens focal length > > translates in your mind to a particular field-of-view. When you crop > > that you haven't changed the effect of the focal length (think: > > squashed depth with a particular telephoto focal length, for example) > > but you HAVE changed the field-of-view. > > Bad choice of example. > > The "squashed depth" effect is a function solely of the combination of > shooting position and angle of view, and nothing to do with focal length. To be pedantic, angle of view doesn't really affect it, either. The relative position and sizes of the objects in the image, which is what creates the depth-compression effect, is entirely determined by the position from which the image is captured. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
J.C. how about trimming irrelevant cruft from your posts? I'm guess that there were about 400 lines of "dead wood", almost half of which were .sigs. On 4/15/2010 10:35 AM, J.C. O'Connell wrote: How many times do I have to tell you to make the point? A zoom has to do much more than a prime so the zoom cannot be "better" or even equal to a prime with BOTH using state of the art designs and optics, period. Whatever they do to improve zoom performance over the years can also be applied to primes. I think that you are confusing physics with market realities. I don't think that anyone is doubting that it would be possible to make a prime that outperforms any of the ultrawide zooms on the market. The reality is that (to a first approximation) nobody is doing so. The lens manufacturers seem to think that nobody is interested in prime lenses. How many image stabilized primes (under 400mm) are made these days? How many prime "kit lenses" are there? The analysis of "would people rather buy three primes to cover the range of 10-20mm or one zoom?" seems to always come up with the answer "one zoom". -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
all else being equal (lens speed, (lens circle/sensor format, barrel size, cost) etc, a SOTA zooom cannot match nor equal a SOTA prime with only one fixed focal length. Its a simpler lens requirement for primes, thats one of the reasons why they still exist, like the DA15 and DA14 -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam Maas Sent: Thursday, April 15, 2010 11:12 AM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms You're clearly not up on the latest developments in lens design. Comparing the best UW prime on the market (The Zeiss 21mm f2.8 Distagon T* in ZK, ZE or ZF mounts) and the best UW zoom on the market, the Nikkor 14-24mm f2.8 G, the zoom has less elements (14 elements in 11 groups for the Nikkor, 16 elements in 13 groups for the Zeiss), although the zoom makes heavy use of exotic glass to achieve this (2 ED elements, 3 aspherical elements, 1 nano-crystal coated element, the latter is unique to Nikon and seriously reduces flare). The Zeiss 21 actually does outperform the Nikkor at 21mm, but only by a small amount (and the zoom has superior flare performance despite its massive front element) and the Zeiss outperforms similar primes by a much larger margin than it does the zoom. Note that the Zeiss 21 is one of the very few truly modern wide prime designs (a 2009 update of a design from 1994), aside from the Pentax DA's, the only other new wide primes are the current set of 14's (Canon's 14LII, the Nikkor 14/2.8D which is the oldest at ~2001 and the brand new Samyang 14/2.8) and Sigma's massive f1.8's (which are good, fast but not exceptional). Simply put, modern molded aspherics, use of low-dispersion elements and other radical tech like Nikon's Nano-crystal coating has functionally removed the advantages of prime designs for wide-angle lenses unless you are trying to make a lens faster than f2.8. The requirements of a retrofocus design simply grow to a point where the requirements for a zoom are irrelevant to anything except size. Making a world class UW requires a very high element count, prime or zoom. Modern digital cameras are simply too demanding for edge performance, particularly high-MP FF cameras. As to the DA 15/4 Limited, it's actually slightly inferior in performance to the DA 14/2.8, and the latter is pretty much identical in performance to the 12-24/4 aside from the extra stop (and the DA 14 is the best performing 14 on APS-C). -Adam On Thu, Apr 15, 2010 at 10:43 AM, J.C. O'Connell wrote: > ultra wide primes require many more elements > than primes do and the results is more flare > they will never match a prime because even > primes need too many elements for high performance > flare performance. > > what is being sold doesnt prove anything other than > market demand. Prime can outdo zooms especially on ultrawides. > > what about the 15mm DA lens?? > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf > Of Adam Maas > Sent: Wednesday, April 14, 2010 7:30 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > LOL, That may have been true 5 years ago, but it simply isn't now. > > Current state of the art in lenses wider than 21mm for SLR mounts are > all zooms. There are no APS-C or 35mm format SLR primes which exceed > the performance of zooms like the Nikkor 14-24/2.8, Zeiss ZA 16-35/2.8 > or either of the 7-14/4'sfrom Oly/Panasonic at focal lengths wider > than 21mm (And the only reason why 21mm matters is the Zeiss 21mm f2.8 > Distagon. which simply dominates the UW prime world for performance). > Current coating technology has greatly reduced the issue of increased > element count (note the Zeiss 21 has an element count which is only > slightly lower than the equivalent zooms) and the increased element > count allows correction of distortion and removal of edge performance > issues which plague even the best older UW primes. > > Most basic wide primes at best match the performance of today's > high-end wide zooms, there have been very few new-design wide primes > introduced in the last 20 years while zoom performance has increased > massively and most zooms in this range are new designs form the last > few years. > > The real downside for us is that none of the best zoom options are > available in K mount. But a zoom like the DA 1
RE: Ultra-wide zooms
How many times do I have to tell you to make the point? A zoom has to do much more than a prime so the zoom cannot be "better" or even equal to a prime with BOTH using state of the art designs and optics, period. Whatever they do to improve zoom performance over the years can also be applied to primes. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam Maas Sent: Thursday, April 15, 2010 11:12 AM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms You're clearly not up on the latest developments in lens design. Comparing the best UW prime on the market (The Zeiss 21mm f2.8 Distagon T* in ZK, ZE or ZF mounts) and the best UW zoom on the market, the Nikkor 14-24mm f2.8 G, the zoom has less elements (14 elements in 11 groups for the Nikkor, 16 elements in 13 groups for the Zeiss), although the zoom makes heavy use of exotic glass to achieve this (2 ED elements, 3 aspherical elements, 1 nano-crystal coated element, the latter is unique to Nikon and seriously reduces flare). The Zeiss 21 actually does outperform the Nikkor at 21mm, but only by a small amount (and the zoom has superior flare performance despite its massive front element) and the Zeiss outperforms similar primes by a much larger margin than it does the zoom. Note that the Zeiss 21 is one of the very few truly modern wide prime designs (a 2009 update of a design from 1994), aside from the Pentax DA's, the only other new wide primes are the current set of 14's (Canon's 14LII, the Nikkor 14/2.8D which is the oldest at ~2001 and the brand new Samyang 14/2.8) and Sigma's massive f1.8's (which are good, fast but not exceptional). Simply put, modern molded aspherics, use of low-dispersion elements and other radical tech like Nikon's Nano-crystal coating has functionally removed the advantages of prime designs for wide-angle lenses unless you are trying to make a lens faster than f2.8. The requirements of a retrofocus design simply grow to a point where the requirements for a zoom are irrelevant to anything except size. Making a world class UW requires a very high element count, prime or zoom. Modern digital cameras are simply too demanding for edge performance, particularly high-MP FF cameras. As to the DA 15/4 Limited, it's actually slightly inferior in performance to the DA 14/2.8, and the latter is pretty much identical in performance to the 12-24/4 aside from the extra stop (and the DA 14 is the best performing 14 on APS-C). -Adam On Thu, Apr 15, 2010 at 10:43 AM, J.C. O'Connell wrote: > ultra wide primes require many more elements > than primes do and the results is more flare > they will never match a prime because even > primes need too many elements for high performance > flare performance. > > what is being sold doesnt prove anything other than > market demand. Prime can outdo zooms especially on ultrawides. > > what about the 15mm DA lens?? > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf > Of Adam Maas > Sent: Wednesday, April 14, 2010 7:30 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > LOL, That may have been true 5 years ago, but it simply isn't now. > > Current state of the art in lenses wider than 21mm for SLR mounts are > all zooms. There are no APS-C or 35mm format SLR primes which exceed > the performance of zooms like the Nikkor 14-24/2.8, Zeiss ZA 16-35/2.8 > or either of the 7-14/4'sfrom Oly/Panasonic at focal lengths wider > than 21mm (And the only reason why 21mm matters is the Zeiss 21mm f2.8 > Distagon. which simply dominates the UW prime world for performance). > Current coating technology has greatly reduced the issue of increased > element count (note the Zeiss 21 has an element count which is only > slightly lower than the equivalent zooms) and the increased element > count allows correction of distortion and removal of edge performance > issues which plague even the best older UW primes. > > Most basic wide primes at best match the performance of today's > high-end wide zooms, there have been very few new-design wide primes > introduced in the last 20 years while zoom performance has increased > massively and most zooms in this range are new designs form the last > few years. > > The real downside for us is that none of the best zoom options are > available in K m
Re: Ultra-wide zooms
On Thu, Apr 15, 2010 at 10:58:23AM -0500, CheekyGeek wrote: > > Well a focal length is a focal length is a focal length but if you are > an old school 35mm film shooter then a particular lens focal length > translates in your mind to a particular field-of-view. When you crop > that you haven't changed the effect of the focal length (think: > squashed depth with a particular telephoto focal length, for example) > but you HAVE changed the field-of-view. Bad choice of example. The "squashed depth" effect is a function solely of the combination of shooting position and angle of view, and nothing to do with focal length. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
As an (important?) aside, I recently bought the Sigma 10-20mm f4-5.6 (used) and read that it WILL cover a full 35mm frame down to 13mm. I plan on trying this myself with my Z-1p. I'm sure the corners will suffer, but WOW... a 13mm rectilinear focal length with no field-of-view crop? If true, it is amazing that they don't promote this. Lesson: Don't ASSUME your lenses designed for APS-C won't cover the full 35mm. They just may not do it over the whole zoom range. > The equivalence is more of a shorthand for photographers who were > accustomed to how 35mm focal lengths worked, and it has really > outlived it's utility. Well a focal length is a focal length is a focal length but if you are an old school 35mm film shooter then a particular lens focal length translates in your mind to a particular field-of-view. When you crop that you haven't changed the effect of the focal length (think: squashed depth with a particular telephoto focal length, for example) but you HAVE changed the field-of-view. For a radical example illustrating this principle, put a F 17-28mm fisheye zoom on a Pentax DSLR. You've still got the fisheye distortion you associate with ultrawide, but you are cropping the center out of the field-of-view (an effective 25-42mm with fisheye curves... which can be very interesting!) Bottom line, if you think in terms of field of view, AND you used to shoot film (or you STILL also shoot film), the equivalence continues to have more than a little utility. It is similar to an older American who will always need to convert metric units to imperial units in order to grasp what is being talked about. A younger generation that simply learned the metric system without having the base knowledge of imperial units would certainly not need that utility. Darren Addy Kearney, NE -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
You're clearly not up on the latest developments in lens design. Comparing the best UW prime on the market (The Zeiss 21mm f2.8 Distagon T* in ZK, ZE or ZF mounts) and the best UW zoom on the market, the Nikkor 14-24mm f2.8 G, the zoom has less elements (14 elements in 11 groups for the Nikkor, 16 elements in 13 groups for the Zeiss), although the zoom makes heavy use of exotic glass to achieve this (2 ED elements, 3 aspherical elements, 1 nano-crystal coated element, the latter is unique to Nikon and seriously reduces flare). The Zeiss 21 actually does outperform the Nikkor at 21mm, but only by a small amount (and the zoom has superior flare performance despite its massive front element) and the Zeiss outperforms similar primes by a much larger margin than it does the zoom. Note that the Zeiss 21 is one of the very few truly modern wide prime designs (a 2009 update of a design from 1994), aside from the Pentax DA's, the only other new wide primes are the current set of 14's (Canon's 14LII, the Nikkor 14/2.8D which is the oldest at ~2001 and the brand new Samyang 14/2.8) and Sigma's massive f1.8's (which are good, fast but not exceptional). Simply put, modern molded aspherics, use of low-dispersion elements and other radical tech like Nikon's Nano-crystal coating has functionally removed the advantages of prime designs for wide-angle lenses unless you are trying to make a lens faster than f2.8. The requirements of a retrofocus design simply grow to a point where the requirements for a zoom are irrelevant to anything except size. Making a world class UW requires a very high element count, prime or zoom. Modern digital cameras are simply too demanding for edge performance, particularly high-MP FF cameras. As to the DA 15/4 Limited, it's actually slightly inferior in performance to the DA 14/2.8, and the latter is pretty much identical in performance to the 12-24/4 aside from the extra stop (and the DA 14 is the best performing 14 on APS-C). -Adam On Thu, Apr 15, 2010 at 10:43 AM, J.C. O'Connell wrote: > ultra wide primes require many more elements > than primes do and the results is more flare > they will never match a prime because even > primes need too many elements for high performance > flare performance. > > what is being sold doesn’t prove anything other than > market demand. Prime can outdo zooms especially on ultrawides. > > what about the 15mm DA lens?? > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam > Maas > Sent: Wednesday, April 14, 2010 7:30 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > LOL, That may have been true 5 years ago, but it simply isn't now. > > Current state of the art in lenses wider than 21mm for SLR mounts are all > zooms. There are no APS-C or 35mm format SLR primes which exceed the > performance of zooms like the Nikkor 14-24/2.8, Zeiss ZA 16-35/2.8 or either > of the 7-14/4'sfrom Oly/Panasonic at focal lengths wider than 21mm (And the > only reason why 21mm matters is the Zeiss 21mm f2.8 Distagon. which simply > dominates the UW prime world for performance). Current coating technology > has greatly reduced the issue of increased element count (note the Zeiss 21 > has an element count which is only slightly lower than the equivalent zooms) > and the increased element count allows correction of distortion and removal > of edge performance issues which plague even the best older UW primes. > > Most basic wide primes at best match the performance of today's high-end > wide zooms, there have been very few new-design wide primes introduced in > the last 20 years while zoom performance has increased massively and most > zooms in this range are new designs form the last few years. > > The real downside for us is that none of the best zoom options are available > in K mount. But a zoom like the DA 12-24/4 or the Sigma 10-20 (in either > form) will match or exceed the performance of almost all the primes in the > same range available in K mount (yes, even the legendary 15/3.5's) on APS-C. > Once again, the Zeiss 21 being the exception (it is available in the ZK > line) but on APS-C it's advantages show a lot less than on 35mm. > > -Adam > > On Mon, Apr 12, 2010 at 3:38 PM, J.C. O'Connell wrote: >> High performance ultra wide zooms (UW) don’t really exist. Go with a >> UW prime and even that wont match basic wide primes. >> >> -- >> J.C. O'Connell (mailto:hifis...@gate.net) >> Join the CD PLAYER & DISC Discussions : &
Re: Ultra-wide zooms
J.C. O'Connell wrote: ultra wide primes sure you meant 'zooms' here require many more elements than primes do and the results is more flare they will never match a prime because even primes need too many elements for high performance flare performance. That's good theory, contradicted by facts. what is being sold doesn't prove anything other than market demand. Prime can outdo zooms especially on ultrawides. In theory they could, but in practice they don't. what about the 15mm DA lens?? Nice lens, outperformed by the DA 12-24. Dario -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
ultra wide primes require many more elements than primes do and the results is more flare they will never match a prime because even primes need too many elements for high performance flare performance. what is being sold doesnt prove anything other than market demand. Prime can outdo zooms especially on ultrawides. what about the 15mm DA lens?? -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Adam Maas Sent: Wednesday, April 14, 2010 7:30 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms LOL, That may have been true 5 years ago, but it simply isn't now. Current state of the art in lenses wider than 21mm for SLR mounts are all zooms. There are no APS-C or 35mm format SLR primes which exceed the performance of zooms like the Nikkor 14-24/2.8, Zeiss ZA 16-35/2.8 or either of the 7-14/4'sfrom Oly/Panasonic at focal lengths wider than 21mm (And the only reason why 21mm matters is the Zeiss 21mm f2.8 Distagon. which simply dominates the UW prime world for performance). Current coating technology has greatly reduced the issue of increased element count (note the Zeiss 21 has an element count which is only slightly lower than the equivalent zooms) and the increased element count allows correction of distortion and removal of edge performance issues which plague even the best older UW primes. Most basic wide primes at best match the performance of today's high-end wide zooms, there have been very few new-design wide primes introduced in the last 20 years while zoom performance has increased massively and most zooms in this range are new designs form the last few years. The real downside for us is that none of the best zoom options are available in K mount. But a zoom like the DA 12-24/4 or the Sigma 10-20 (in either form) will match or exceed the performance of almost all the primes in the same range available in K mount (yes, even the legendary 15/3.5's) on APS-C. Once again, the Zeiss 21 being the exception (it is available in the ZK line) but on APS-C it's advantages show a lot less than on 35mm. -Adam On Mon, Apr 12, 2010 at 3:38 PM, J.C. O'Connell wrote: > High performance ultra wide zooms (UW) dont really exist. Go with a > UW prime and even that wont match basic wide primes. > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf > Of David Parsons > Sent: Monday, April 12, 2010 3:12 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > There are two common crops for dSLRs as compared to FF SLR, 1.5 (Nikon > and > Pentax) and 1.6 (Canon). > > Canon has a 1.3 crop on some of their pro bodies. > > P&S sensors are a whole other barrel of fish and there are many sizes, > but they don't correlate because the lenses are not interchangeable. > > On Mon, Apr 12, 2010 at 3:00 PM, Keith Whaley > wrote: >> P N Stenquist wrote: >>> >>> On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: >>> >>>> Bong Manayon wrote: >>>>> >>>>> Thinking of ... >>>>> 1. Pentax DA 12-24 >>>>> 2. Sigma 10-20 >>>>> 3. Tamron 10-24 >>>>> Am not into fish-eyes so those options are out. Any votes for or >>>>> against any of those listed above? Thanks! Bong >> >>>> I don't think those focal lengths are 35mm-equivalent numbers. I >>>> suspect they're double ~ such as the Pentax DA 12-24 is really like >>>> a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal >>>> lens, but hardly a fish-eye... >> >>> First, the conversion factor for angle of view is 1.5. >> >> Was Bong talking about a specific camera? I know we were talking >> digitals, but, I thought each camera had it's own conversion camera. >> In my limited experience, which does NOT include DSLRs, most cameras >> differ a little as to what their 35mm equivalent is. I avoid the >> uncertainty by referring to the owner's manual for each camera. They >> always mention it... >> >>> So the 12-24 has the same _angle of view_ on an APS-C DSLR as an >>> 18-36 would have on a conventional 35 mm frame. >> >> Cropping factor, or what I call the telephoto effect, brought on by >> the size of the sensor. In other
Re: Ultra-wide zooms
LOL, That may have been true 5 years ago, but it simply isn't now. Current state of the art in lenses wider than 21mm for SLR mounts are all zooms. There are no APS-C or 35mm format SLR primes which exceed the performance of zooms like the Nikkor 14-24/2.8, Zeiss ZA 16-35/2.8 or either of the 7-14/4'sfrom Oly/Panasonic at focal lengths wider than 21mm (And the only reason why 21mm matters is the Zeiss 21mm f2.8 Distagon. which simply dominates the UW prime world for performance). Current coating technology has greatly reduced the issue of increased element count (note the Zeiss 21 has an element count which is only slightly lower than the equivalent zooms) and the increased element count allows correction of distortion and removal of edge performance issues which plague even the best older UW primes. Most basic wide primes at best match the performance of today's high-end wide zooms, there have been very few new-design wide primes introduced in the last 20 years while zoom performance has increased massively and most zooms in this range are new designs form the last few years. The real downside for us is that none of the best zoom options are available in K mount. But a zoom like the DA 12-24/4 or the Sigma 10-20 (in either form) will match or exceed the performance of almost all the primes in the same range available in K mount (yes, even the legendary 15/3.5's) on APS-C. Once again, the Zeiss 21 being the exception (it is available in the ZK line) but on APS-C it's advantages show a lot less than on 35mm. -Adam On Mon, Apr 12, 2010 at 3:38 PM, J.C. O'Connell wrote: > High performance ultra wide zooms (UW) don’t really exist. Go with a UW > prime > and even that wont match basic wide primes. > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of > David Parsons > Sent: Monday, April 12, 2010 3:12 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > There are two common crops for dSLRs as compared to FF SLR, 1.5 (Nikon and > Pentax) and 1.6 (Canon). > > Canon has a 1.3 crop on some of their pro bodies. > > P&S sensors are a whole other barrel of fish and there are many sizes, but > they don't correlate because the lenses are not interchangeable. > > On Mon, Apr 12, 2010 at 3:00 PM, Keith Whaley > wrote: >> P N Stenquist wrote: >>> >>> On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: >>> >>>> Bong Manayon wrote: >>>>> >>>>> Thinking of ... >>>>> 1. Pentax DA 12-24 >>>>> 2. Sigma 10-20 >>>>> 3. Tamron 10-24 >>>>> Am not into fish-eyes so those options are out. Any votes for or >>>>> against any of those listed above? Thanks! >>>>> Bong >> >>>> I don't think those focal lengths are 35mm-equivalent numbers. I >>>> suspect they're double ~ such as the Pentax DA 12-24 is really like >>>> a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal lens, >>>> but hardly a fish-eye... >> >>> First, the conversion factor for angle of view is 1.5. >> >> Was Bong talking about a specific camera? I know we were talking >> digitals, but, I thought each camera had it's own conversion camera. >> In my limited experience, which does NOT include DSLRs, most cameras >> differ a little as to what their 35mm equivalent is. I avoid the >> uncertainty by referring to the owner's manual for each camera. They >> always mention it... >> >>> So the 12-24 has the same _angle of view_ on an APS-C DSLR as an >>> 18-36 would have on a conventional 35 mm frame. >> >> Cropping factor, or what I call the telephoto effect, brought on by >> the size of the sensor. In other words, the ratio derives from how >> much smaller the DSLR's sensor is compared to 35mm film size. >> See: >> >> http://www.minasi.com/photos/dslrmag/ >> >>> However, the focal length is 12-24. That doesn't change, regardless >>> of the format. Furthermore, it's not a fisheye on any format. It's a >>> rectilinear lens. In other words, the optics make the verticals as >>> true as possible given the size of the elements and the constraints >>> of physical science. Paul >> >> Quite so. Thanks Paul. >> >> keith whaley >> >> >> -- >> PDML Pentax-Discuss Mail List >> PDML@pdml.net >> http
RE: Ultra-wide zooms [Scanned][Spam score:8%]
I've had the earlier one for a few years now and I'm completely satisfied with the performance, the build quality is great too. John From: pdml-boun...@pdml.net [pdml-boun...@pdml.net] On Behalf Of Bong Manayon [bongmana...@gmail.com] Sent: 12 April 2010 22:48 To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms [Scanned][Spam score:8%] On Mon, Apr 12, 2010 at 11:26 PM, John Sessoms wrote: > > The Sigma 10-20 comes in two versions f/4-5.6 & a constant aperture f/3.5. > > I have the former and am quite pleased with it, although I'm still learning > when and how to use it to maximum advantage. A lot of people badmouth Sigma > lenses, but the build quality on this lens is rock solid. > > I have the Pentax FAJ 18-35 that I consider a really sloppy lens, and the > Sigma is miles above it in quality. > Thanks! The one I'm trying out now is the 4-5.6 and it impresses me--and I admit I'm biased against Sigma (had bad experience way back with their quality control problem). Bong -- Bong Manayon http://www.bong.uni.cc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
2010/4/13 P. J. Alling : > > Ecke, have you been taking spelling lessons from Brooks? I'd most certainly feel very honoured had that been the case but no =P -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Bong Manayon wrote: Thinking of ... 1. Pentax DA 12-24 2. Sigma 10-20 3. Tamron 10-24 Am not into fish-eyes so those options are out. Any votes for or against any of those listed above? Thanks! Bong I have the 12-24. It never disappoints me. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Bong - Here is a shot with the Pentax 12-24. (somewhat cropped.) http://photos.stanhalpin.com/p155717848/e260095cd I don't have much experience with this lens, I borrowed my brother's for a day, at the end of which I tried to trade him one of my longer lenses for it. Very nice lens. No experience at all with the off-brand lenses. stan On Apr 12, 2010, at 4:45 AM, Bong Manayon wrote: > Thinking of ... > > 1. Pentax DA 12-24 > 2. Sigma 10-20 > 3. Tamron 10-24 > > Am not into fish-eyes so those options are out. Any votes for or > against any of those listed above? > > Thanks! > > Bong > > -- > Bong Manayon > http://www.bong.uni.cc > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Ecke, have you been taking spelling lessons from Brooks?
On 4/12/2010 6:13 AM, eckinator wrote:
Asked myself the same question to be prepared for when I have money to
burn and the DA* 11-16 is still not there...
Result I found in reviews and forum discussions (Caveat: this is hands
off information):
1. Best build, sharpest, most neutral color rendition, however pricey as hell
2. Worst haptics, bit darker than 3. but better corner sharpness and
better wide open
3. Better haptics then 2., stpo down recommended to at least 5.6 for
sharpness, longest warranty (5 yrs over here)
Over here you can buy two to three shmegma or spamron lenses for one
paytax so I could buy 2. AND 3. and still have money left for other
stuff... =(
HTH
Ecke
2010/4/12 Bong Manayon:
Thinking of ...
1. Pentax DA 12-24
2. Sigma 10-20
3. Tamron 10-24
Am not into fish-eyes so those options are out. Any votes for or
against any of those listed above?
Thanks!
Bong
--
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http://www.bong.uni.cc
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Re: Ultra-wide zooms
On Tue, Apr 13, 2010 at 09:26:43AM +1000, Tanya Love wrote: > I thought that "equivalents" were only if you were using FA lenses? I > thought that the Das removed this need to "convert"? > > Tan. Not so. This is why thinking of it as a "focal length conversion" is bad. A DA 50mm lens is a 50mm lens, and acts just the same as an FA 50mm lens. Both will cover the same angle of view whe mounted to a particular body. The "focal length multiplier", "conversion factor", "equivalent focal length", or whatever comes when you try and use two different cameras with different sized sensors (where a frame of film is also a sensor). Using a 50mm focal length lens on a camera with a 24x16mm sensor (such as the Pentax DSLRs) will not cover the same angle of view as when using the same lens on a camera with a 36x24mm sensor - it will be exactly the same as creating an image from the central 24x16mm portion of the larger sensor (because that is, in fact, what you are doing). This is basically what you would get if you used a 75mm lens with that larger sensor (at least as far as angle of view is concerned). -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
angles, focal lengths, and sensor sizes are all there is and you cant ignore any of the three dimensions -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Tanya Love Sent: Monday, April 12, 2010 7:27 PM To: 'Pentax-Discuss Mail List' Subject: RE: Ultra-wide zooms I thought that "equivalents" were only if you were using FA lenses? I thought that the Das removed this need to "convert"? Tan. -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Bong Manayon Sent: Monday, 12 April 2010 11:29 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms On Mon, Apr 12, 2010 at 9:17 PM, David Parsons wrote: > Please repeat after me: There is no such thing as equivalent focal length! > > They are APS-C lenses and the focal lengths are as marked. Super wide > angle lenses. > Amen. I take those numbers for their face value. I stopped thinking of equivalents a long time ago. Bong -- Bong Manayon http://www.bong.uni.cc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. __ Information from ESET NOD32 Antivirus, version of virus signature database 5021 (20100412) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
There is nothing to convert because the focal length doesn't change. The equivalence is more of a shorthand for photographers who were accustomed to how 35mm focal lengths worked, and it has really outlived it's utility. On Mon, Apr 12, 2010 at 7:26 PM, Tanya Love wrote: > I thought that "equivalents" were only if you were using FA lenses? I > thought that the Das removed this need to "convert"? > > Tan. > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Bong > Manayon > Sent: Monday, 12 April 2010 11:29 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > On Mon, Apr 12, 2010 at 9:17 PM, David Parsons > wrote: >> Please repeat after me: There is no such thing as equivalent focal > length! >> >> They are APS-C lenses and the focal lengths are as marked. Super wide >> angle lenses. >> > > Amen. > > I take those numbers for their face value. I stopped thinking of > equivalents a long time ago. > > Bong > > -- > Bong Manayon > http://www.bong.uni.cc > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > > __ Information from ESET NOD32 Antivirus, version of virus signature > database 5021 (20100412) __ > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
I thought that "equivalents" were only if you were using FA lenses? I thought that the Das removed this need to "convert"? Tan. -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Bong Manayon Sent: Monday, 12 April 2010 11:29 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms On Mon, Apr 12, 2010 at 9:17 PM, David Parsons wrote: > Please repeat after me: There is no such thing as equivalent focal length! > > They are APS-C lenses and the focal lengths are as marked. Super wide > angle lenses. > Amen. I take those numbers for their face value. I stopped thinking of equivalents a long time ago. Bong -- Bong Manayon http://www.bong.uni.cc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. __ Information from ESET NOD32 Antivirus, version of virus signature database 5021 (20100412) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On Mon, Apr 12, 2010 at 11:26 PM, John Sessoms wrote: > > The Sigma 10-20 comes in two versions f/4-5.6 & a constant aperture f/3.5. > > I have the former and am quite pleased with it, although I'm still learning > when and how to use it to maximum advantage. A lot of people badmouth Sigma > lenses, but the build quality on this lens is rock solid. > > I have the Pentax FAJ 18-35 that I consider a really sloppy lens, and the > Sigma is miles above it in quality. > Thanks! The one I'm trying out now is the 4-5.6 and it impresses me--and I admit I'm biased against Sigma (had bad experience way back with their quality control problem). Bong -- Bong Manayon http://www.bong.uni.cc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Not really replying to JCO, just tagging into the thread here. The students in my class usually don't quite get the difference in sensor sizes and the relationship to focal length until they see the circular photo towards the bottom of this page. It superimposes three sensor sizes over the circular image projected by a lens. <http://www.shortcourses.com/use/using5-2.html> Once they see this, they get it pretty quick. GS George Sinos gsi...@gmail.com www.georgesphotos.net On Mon, Apr 12, 2010 at 3:28 PM, J.C. O'Connell wrote: > a 12mm lens on APS is not as wide as a 15mm lens on FF > hence, the A15mm wont perform as well on on FF or even > APS as a 12mm on APS. (in general). The problem is that > it takes to many elements which hurts the flaring reduction. > Cost and lens speed are also factors. I would bet the > DA 15mm outperforms the A15 on APS as the DA15 isnt > designed to cover FF like the A15 is so it can be tweeked > for Aps. > > -- > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of P N > Stenquist > Sent: Monday, April 12, 2010 3:52 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > > On Apr 12, 2010, at 3:38 PM, J.C. O'Connell wrote: > >> High performance ultra wide zooms (UW) don't really exist. Go with a >> UW >> prime >> and even that wont match basic wide primes. >> >> -- > The DA 12-24/4 is reportedly comparable in performance to the DA > 14/2.8, although it's a stop slower. I've also read that it's actually > better than the A 15/3.5 at comparable FOV. I haven't compared it > directly to either, but I know from experience that it's an excellent > lens, capable of generating a nice, crisp double page spread at 12mm. > Good tool. > Paul > >> J.C. O'Connell (mailto:hifis...@gate.net) >> Join the CD PLAYER & DISC Discussions : >> http://tech.groups.yahoo.com/group/cdplayers/ >> http://launch.groups.yahoo.com/group/cdsound/ >> >> >> -Original Message- >> From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf >> Of >> David Parsons >> Sent: Monday, April 12, 2010 3:12 PM >> To: Pentax-Discuss Mail List >> Subject: Re: Ultra-wide zooms >> >> >> There are two common crops for dSLRs as compared to FF SLR, 1.5 >> (Nikon and >> Pentax) and 1.6 (Canon). >> >> Canon has a 1.3 crop on some of their pro bodies. >> >> P&S sensors are a whole other barrel of fish and there are many >> sizes, but >> they don't correlate because the lenses are not interchangeable. >> >> On Mon, Apr 12, 2010 at 3:00 PM, Keith Whaley >> wrote: >>> P N Stenquist wrote: >>>> >>>> On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: >>>> >>>>> Bong Manayon wrote: >>>>>> >>>>>> Thinking of ... >>>>>> 1. Pentax DA 12-24 >>>>>> 2. Sigma 10-20 >>>>>> 3. Tamron 10-24 >>>>>> Am not into fish-eyes so those options are out. Any votes for or >>>>>> against any of those listed above? Thanks! >>>>>> Bong >>> >>>>> I don't think those focal lengths are 35mm-equivalent numbers. I >>>>> suspect they're double ~ such as the Pentax DA 12-24 is really like >>>>> a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal >>>>> lens, >>>>> but hardly a fish-eye... >>> >>>> First, the conversion factor for angle of view is 1.5. >>> >>> Was Bong talking about a specific camera? I know we were talking >>> digitals, but, I thought each camera had it's own conversion camera. >>> In my limited experience, which does NOT include DSLRs, most cameras >>> differ a little as to what their 35mm equivalent is. I avoid the >>> uncertainty by referring to the owner's manual for each camera. They >>> always mention it... >>> >>>> So the 12-24 has the same _angle of view_ on an APS-C DSLR as an >>>> 18-36 would have on a conventional 35 mm frame. >>> >>> Cropping factor, or what I call the telephoto effect, brought on by >>> the size of the sensor. In other words, the ratio derives from how >>> much smaller the DSLR's sensor
RE: Ultra-wide zooms
a 12mm lens on APS is not as wide as a 15mm lens on FF hence, the A15mm wont perform as well on on FF or even APS as a 12mm on APS. (in general). The problem is that it takes to many elements which hurts the flaring reduction. Cost and lens speed are also factors. I would bet the DA 15mm outperforms the A15 on APS as the DA15 isnt designed to cover FF like the A15 is so it can be tweeked for Aps. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of P N Stenquist Sent: Monday, April 12, 2010 3:52 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms On Apr 12, 2010, at 3:38 PM, J.C. O'Connell wrote: > High performance ultra wide zooms (UW) don't really exist. Go with a > UW > prime > and even that wont match basic wide primes. > > -- The DA 12-24/4 is reportedly comparable in performance to the DA 14/2.8, although it's a stop slower. I've also read that it's actually better than the A 15/3.5 at comparable FOV. I haven't compared it directly to either, but I know from experience that it's an excellent lens, capable of generating a nice, crisp double page spread at 12mm. Good tool. Paul > J.C. O'Connell (mailto:hifis...@gate.net) > Join the CD PLAYER & DISC Discussions : > http://tech.groups.yahoo.com/group/cdplayers/ > http://launch.groups.yahoo.com/group/cdsound/ > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf > Of > David Parsons > Sent: Monday, April 12, 2010 3:12 PM > To: Pentax-Discuss Mail List > Subject: Re: Ultra-wide zooms > > > There are two common crops for dSLRs as compared to FF SLR, 1.5 > (Nikon and > Pentax) and 1.6 (Canon). > > Canon has a 1.3 crop on some of their pro bodies. > > P&S sensors are a whole other barrel of fish and there are many > sizes, but > they don't correlate because the lenses are not interchangeable. > > On Mon, Apr 12, 2010 at 3:00 PM, Keith Whaley > wrote: >> P N Stenquist wrote: >>> >>> On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: >>> >>>> Bong Manayon wrote: >>>>> >>>>> Thinking of ... >>>>> 1. Pentax DA 12-24 >>>>> 2. Sigma 10-20 >>>>> 3. Tamron 10-24 >>>>> Am not into fish-eyes so those options are out. Any votes for or >>>>> against any of those listed above? Thanks! >>>>> Bong >> >>>> I don't think those focal lengths are 35mm-equivalent numbers. I >>>> suspect they're double ~ such as the Pentax DA 12-24 is really like >>>> a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal >>>> lens, >>>> but hardly a fish-eye... >> >>> First, the conversion factor for angle of view is 1.5. >> >> Was Bong talking about a specific camera? I know we were talking >> digitals, but, I thought each camera had it's own conversion camera. >> In my limited experience, which does NOT include DSLRs, most cameras >> differ a little as to what their 35mm equivalent is. I avoid the >> uncertainty by referring to the owner's manual for each camera. They >> always mention it... >> >>> So the 12-24 has the same _angle of view_ on an APS-C DSLR as an >>> 18-36 would have on a conventional 35 mm frame. >> >> Cropping factor, or what I call the telephoto effect, brought on by >> the size of the sensor. In other words, the ratio derives from how >> much smaller the DSLR's sensor is compared to 35mm film size. >> See: >> >> http://www.minasi.com/photos/dslrmag/ >> >>> However, the focal length is 12-24. That doesn't change, regardless >>> of the format. Furthermore, it's not a fisheye on any format. It's a >>> rectilinear lens. In other words, the optics make the verticals as >>> true as possible given the size of the elements and the constraints >>> of physical science. Paul >> >> Quite so. Thanks Paul. >> >> keith whaley >> >> >> -- >> PDML Pentax-Discuss Mail List >> PDML@pdml.net >> http://pdml.net/mailman/listinfo/pdml_pdml.net >> to UNSUBSCRIBE from the PDML, please visit the link directly above >> and >> follow the directions. >> > > > > -- > Aloha Photographer Photoblog > http://alohaphotog.blogspot.com/ > > -- > PDML Pentax-Discuss Mail List > PDML@p
Re: Ultra-wide zooms
On Apr 12, 2010, at 3:38 PM, J.C. O'Connell wrote: High performance ultra wide zooms (UW) don’t really exist. Go with a UW prime and even that wont match basic wide primes. -- The DA 12-24/4 is reportedly comparable in performance to the DA 14/2.8, although it's a stop slower. I've also read that it's actually better than the A 15/3.5 at comparable FOV. I haven't compared it directly to either, but I know from experience that it's an excellent lens, capable of generating a nice, crisp double page spread at 12mm. Good tool. Paul J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of David Parsons Sent: Monday, April 12, 2010 3:12 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms There are two common crops for dSLRs as compared to FF SLR, 1.5 (Nikon and Pentax) and 1.6 (Canon). Canon has a 1.3 crop on some of their pro bodies. P&S sensors are a whole other barrel of fish and there are many sizes, but they don't correlate because the lenses are not interchangeable. On Mon, Apr 12, 2010 at 3:00 PM, Keith Whaley wrote: P N Stenquist wrote: On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: Bong Manayon wrote: Thinking of ... 1. Pentax DA 12-24 2. Sigma 10-20 3. Tamron 10-24 Am not into fish-eyes so those options are out. Any votes for or against any of those listed above? Thanks! Bong I don't think those focal lengths are 35mm-equivalent numbers. I suspect they're double ~ such as the Pentax DA 12-24 is really like a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal lens, but hardly a fish-eye... First, the conversion factor for angle of view is 1.5. Was Bong talking about a specific camera? I know we were talking digitals, but, I thought each camera had it's own conversion camera. In my limited experience, which does NOT include DSLRs, most cameras differ a little as to what their 35mm equivalent is. I avoid the uncertainty by referring to the owner's manual for each camera. They always mention it... So the 12-24 has the same _angle of view_ on an APS-C DSLR as an 18-36 would have on a conventional 35 mm frame. Cropping factor, or what I call the telephoto effect, brought on by the size of the sensor. In other words, the ratio derives from how much smaller the DSLR's sensor is compared to 35mm film size. See: http://www.minasi.com/photos/dslrmag/ However, the focal length is 12-24. That doesn't change, regardless of the format. Furthermore, it's not a fisheye on any format. It's a rectilinear lens. In other words, the optics make the verticals as true as possible given the size of the elements and the constraints of physical science. Paul Quite so. Thanks Paul. keith whaley -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: Ultra-wide zooms
High performance ultra wide zooms (UW) dont really exist. Go with a UW prime and even that wont match basic wide primes. -- J.C. O'Connell (mailto:hifis...@gate.net) Join the CD PLAYER & DISC Discussions : http://tech.groups.yahoo.com/group/cdplayers/ http://launch.groups.yahoo.com/group/cdsound/ -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of David Parsons Sent: Monday, April 12, 2010 3:12 PM To: Pentax-Discuss Mail List Subject: Re: Ultra-wide zooms There are two common crops for dSLRs as compared to FF SLR, 1.5 (Nikon and Pentax) and 1.6 (Canon). Canon has a 1.3 crop on some of their pro bodies. P&S sensors are a whole other barrel of fish and there are many sizes, but they don't correlate because the lenses are not interchangeable. On Mon, Apr 12, 2010 at 3:00 PM, Keith Whaley wrote: > P N Stenquist wrote: >> >> On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: >> >>> Bong Manayon wrote: >>>> >>>> Thinking of ... >>>> 1. Pentax DA 12-24 >>>> 2. Sigma 10-20 >>>> 3. Tamron 10-24 >>>> Am not into fish-eyes so those options are out. Any votes for or >>>> against any of those listed above? Thanks! >>>> Bong > >>> I don't think those focal lengths are 35mm-equivalent numbers. I >>> suspect they're double ~ such as the Pentax DA 12-24 is really like >>> a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal lens, >>> but hardly a fish-eye... > >> First, the conversion factor for angle of view is 1.5. > > Was Bong talking about a specific camera? I know we were talking > digitals, but, I thought each camera had it's own conversion camera. > In my limited experience, which does NOT include DSLRs, most cameras > differ a little as to what their 35mm equivalent is. I avoid the > uncertainty by referring to the owner's manual for each camera. They > always mention it... > >> So the 12-24 has the same _angle of view_ on an APS-C DSLR as an >> 18-36 would have on a conventional 35 mm frame. > > Cropping factor, or what I call the telephoto effect, brought on by > the size of the sensor. In other words, the ratio derives from how > much smaller the DSLR's sensor is compared to 35mm film size. > See: > > http://www.minasi.com/photos/dslrmag/ > >> However, the focal length is 12-24. That doesn't change, regardless >> of the format. Furthermore, it's not a fisheye on any format. It's a >> rectilinear lens. In other words, the optics make the verticals as >> true as possible given the size of the elements and the constraints >> of physical science. Paul > > Quite so. Thanks Paul. > > keith whaley > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
There are two common crops for dSLRs as compared to FF SLR, 1.5 (Nikon and Pentax) and 1.6 (Canon). Canon has a 1.3 crop on some of their pro bodies. P&S sensors are a whole other barrel of fish and there are many sizes, but they don't correlate because the lenses are not interchangeable. On Mon, Apr 12, 2010 at 3:00 PM, Keith Whaley wrote: > P N Stenquist wrote: >> >> On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: >> >>> Bong Manayon wrote: Thinking of ... 1. Pentax DA 12-24 2. Sigma 10-20 3. Tamron 10-24 Am not into fish-eyes so those options are out. Any votes for or against any of those listed above? Thanks! Bong > >>> I don't think those focal lengths are 35mm-equivalent numbers. I suspect >>> they're double ~ such as the Pentax DA 12-24 is really like a 35mm lens of >>> 24-48mm focal length. >>> Nice wide angle-to-normal lens, but hardly a fish-eye... > >> First, the conversion factor for angle of view is 1.5. > > Was Bong talking about a specific camera? I know we were talking digitals, > but, I thought each camera had it's own conversion camera. In my limited > experience, which does NOT include DSLRs, most cameras differ a little as to > what their 35mm equivalent is. > I avoid the uncertainty by referring to the owner's manual for each camera. > They always mention it... > >> So the 12-24 has the same _angle of view_ on an APS-C DSLR >> as an 18-36 would have on a conventional 35 mm frame. > > Cropping factor, or what I call the telephoto effect, brought on by the size > of the sensor. In other words, the ratio derives from how much smaller the > DSLR's sensor is compared to 35mm film size. > See: > > http://www.minasi.com/photos/dslrmag/ > >> However, the focal length is 12-24. That doesn't change, regardless of the >> format. Furthermore, it's not a fisheye on any format. It's a rectilinear >> lens. In other words, the optics make the verticals as true as possible >> given the size of the elements and the constraints of physical science. >> Paul > > Quite so. Thanks Paul. > > keith whaley > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
P N Stenquist wrote: On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: Bong Manayon wrote: Thinking of ... 1. Pentax DA 12-24 2. Sigma 10-20 3. Tamron 10-24 Am not into fish-eyes so those options are out. Any votes for or against any of those listed above? Thanks! Bong I don't think those focal lengths are 35mm-equivalent numbers. I suspect they're double ~ such as the Pentax DA 12-24 is really like a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal lens, but hardly a fish-eye... First, the conversion factor for angle of view is 1.5. Was Bong talking about a specific camera? I know we were talking digitals, but, I thought each camera had it's own conversion camera. In my limited experience, which does NOT include DSLRs, most cameras differ a little as to what their 35mm equivalent is. I avoid the uncertainty by referring to the owner's manual for each camera. They always mention it... So the 12-24 has the same _angle of view_ on an APS-C DSLR as an 18-36 would have on a conventional 35 mm frame. Cropping factor, or what I call the telephoto effect, brought on by the size of the sensor. In other words, the ratio derives from how much smaller the DSLR's sensor is compared to 35mm film size. See: http://www.minasi.com/photos/dslrmag/ However, the focal length is 12-24. That doesn't change, regardless of the format. Furthermore, it's not a fisheye on any format. It's a rectilinear lens. In other words, the optics make the verticals as true as possible given the size of the elements and the constraints of physical science. Paul Quite so. Thanks Paul. keith whaley -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On 12/4/10, David Parsons, discombobulated, unleashed: >Please repeat after me: There is no such thing as equivalent focal length! > >They are APS-C lenses and the focal lengths are as marked. Super wide >angle lenses. Very true, come on people!!! But if they were equivalent focal lengths, they would be: 1. Pentax DA 18-36 2. Sigma 15-30 3. Tamron 15-36 -- Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche -- http://www.cottysnaps.com _ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
From: P N Stenquist On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: > Bong Manayon wrote: >> Thinking of ... >> 1. Pentax DA 12-24 >> 2. Sigma 10-20 >> 3. Tamron 10-24 >> Am not into fish-eyes so those options are out. Any votes for or >> against any of those listed above? >> Thanks! >> Bong > > I don't think those focal lengths are 35mm-equivalent numbers. I > suspect they're double ~ such as the Pentax DA 12-24 is really like > a 35mm lens of 24-48mm focal length. > Nice wide angle-to-normal lens, but hardly a fish-eye... > First, the conversion factor for angle of view is 1.5. So the 12-24 has the same angle of view on an APS-C DSLR as an 18-36 would have on a conventional 35 mm frame. However, the focal length is 12-24. That doesn't change, regardless of the format. Furthermore, it's not a fisheye on any format. It's a rectilinear lens. In other words, the optics make the verticals as true as possible given the size of the elements and the constraints of physical science. Paul The Sigma 10-20 comes in two versions f/4-5.6 & a constant aperture f/3.5. I have the former and am quite pleased with it, although I'm still learning when and how to use it to maximum advantage. A lot of people badmouth Sigma lenses, but the build quality on this lens is rock solid. I have the Pentax FAJ 18-35 that I consider a really sloppy lens, and the Sigma is miles above it in quality. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On Mon, Apr 12, 2010 at 9:17 PM, David Parsons wrote: > Please repeat after me: There is no such thing as equivalent focal length! > > They are APS-C lenses and the focal lengths are as marked. Super wide > angle lenses. > Amen. I take those numbers for their face value. I stopped thinking of equivalents a long time ago. Bong -- Bong Manayon http://www.bong.uni.cc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On Mon, Apr 12, 2010 at 8:48 PM, Keith Whaley wrote: > > I don't think those focal lengths are 35mm-equivalent numbers. I suspect > they're double ~ such as the Pentax DA 12-24 is really like a 35mm lens of > 24-48mm focal length. > Nice wide angle-to-normal lens, but hardly a fish-eye... > > keith whaley > Was I ambiguous? I did not want a fish-eye but a rectilinear lens and my choices were the ones listed above. The DA seems to be the obvious but expensive choice; I'm currently using a borrowed Sigma 10-20 but want to hear anyone else' experience with it as well as the Tamron. Bong -- Bong Manayon http://www.bong.uni.cc -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
On Apr 12, 2010, at 8:48 AM, Keith Whaley wrote: Bong Manayon wrote: Thinking of ... 1. Pentax DA 12-24 2. Sigma 10-20 3. Tamron 10-24 Am not into fish-eyes so those options are out. Any votes for or against any of those listed above? Thanks! Bong I don't think those focal lengths are 35mm-equivalent numbers. I suspect they're double ~ such as the Pentax DA 12-24 is really like a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal lens, but hardly a fish-eye... First, the conversion factor for angle of view is 1.5. So the 12-24 has the same angle of view on an APS-C DSLR as an 18-36 would have on a conventional 35 mm frame. However, the focal length is 12-24. That doesn't change, regardless of the format. Furthermore, it's not a fisheye on any format. It's a rectilinear lens. In other words, the optics make the verticals as true as possible given the size of the elements and the constraints of physical science. Paul keith whaley -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Please repeat after me: There is no such thing as equivalent focal length! They are APS-C lenses and the focal lengths are as marked. Super wide angle lenses. On Mon, Apr 12, 2010 at 8:48 AM, Keith Whaley wrote: > Bong Manayon wrote: >> >> Thinking of ... >> >> 1. Pentax DA 12-24 >> 2. Sigma 10-20 >> 3. Tamron 10-24 >> >> Am not into fish-eyes so those options are out. Any votes for or >> against any of those listed above? >> >> Thanks! >> >> Bong >> > > I don't think those focal lengths are 35mm-equivalent numbers. I suspect > they're double ~ such as the Pentax DA 12-24 is really like a 35mm lens of > 24-48mm focal length. > Nice wide angle-to-normal lens, but hardly a fish-eye... > > keith whaley > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Bong Manayon wrote: Thinking of ... 1. Pentax DA 12-24 2. Sigma 10-20 3. Tamron 10-24 Am not into fish-eyes so those options are out. Any votes for or against any of those listed above? Thanks! Bong I don't think those focal lengths are 35mm-equivalent numbers. I suspect they're double ~ such as the Pentax DA 12-24 is really like a 35mm lens of 24-48mm focal length. Nice wide angle-to-normal lens, but hardly a fish-eye... keith whaley -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
DA 12-24! The reviews are spot on. I grabbed one before Pentax raised the price to DA* levels. You could also switch to the dark side and grab a Tokina 12-24 for canon or nikon. Used prices for the Tokina are max 300-350 euro. I see a new (used) Tokina every 1-2 weeks. The DA version is 1050 euro new! On 12 April 2010 11:45, Bong Manayon wrote: > Thinking of ... > > 1. Pentax DA 12-24 > 2. Sigma 10-20 > 3. Tamron 10-24 > > Am not into fish-eyes so those options are out. Any votes for or > against any of those listed above? > > Thanks! > > Bong > > -- > Bong Manayon > http://www.bong.uni.cc > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Ultra-wide zooms
Asked myself the same question to be prepared for when I have money to burn and the DA* 11-16 is still not there... Result I found in reviews and forum discussions (Caveat: this is hands off information): 1. Best build, sharpest, most neutral color rendition, however pricey as hell 2. Worst haptics, bit darker than 3. but better corner sharpness and better wide open 3. Better haptics then 2., stpo down recommended to at least 5.6 for sharpness, longest warranty (5 yrs over here) Over here you can buy two to three shmegma or spamron lenses for one paytax so I could buy 2. AND 3. and still have money left for other stuff... =( HTH Ecke 2010/4/12 Bong Manayon : > Thinking of ... > > 1. Pentax DA 12-24 > 2. Sigma 10-20 > 3. Tamron 10-24 > > Am not into fish-eyes so those options are out. Any votes for or > against any of those listed above? > > Thanks! > > Bong > > -- > Bong Manayon > http://www.bong.uni.cc > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. > -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
