RE: Pentax AF Lens + SF7 = DSLR
Just be careful with 3rd party lenses I have a sigma AF 24-70 zoom lens that works well on my MZ7 but won't work on any Pentax SLR camera built after the year 2000. James -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Peter Sent: Monday, 25 May 2009 6:14 PM To: Pentax-Discuss Mail List Subject: Re: Pentax AF Lens + SF7 = DSLR Thanks all for the "speedy" replies Nice to see the old lenses can still be utilized, this is a definite bonus to now being able to set more aside for a "Body Only" Pentax deal. Just find that my current Olympus C-730 UltraZoom 10x Optical is "slow" to respond to zoom and focus (by today's standards) and it was purchased as more of a "crossover" functionality between a P&S snapper to some fine telephoto capabilities, and has served me well. Thanks Peter D (Adelaide) John Coyle wrote: > Peter, those lenses should work well, as others have already said. I have a > Tokina 400/5.6 MF lens which is very good on digital. The K7 has a built-in > focus assist light, and some of the Pentax flashes, such as the AF-330FTZ, > will throw a low-intensity red beam to ensure accurate focus. > > HTH > > > John in Brisbane > > > > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of > Peter > Sent: Monday, 25 May 2009 2:47 PM > To: PDML@pdml.net > Subject: Pentax AF Lens + SF7 = DSLR > > Have a Pentax SF7 (film) camera with a SMC Pentax-F Zoom 35-70 f3.5 AF) > > (Also have a Tokina 70-210 f4.5 AF) > > Are these lenses usable on any Pentax Digital SLR's? I am currently > investigating at upgrading to Digital SLR. > > Am particularly interested in the new K-7 (still waiting for pricing in > Australia) or the K-m. > > The feature I liked most about my old SF7 was the "AF spotbeam" which > assisted with auto-focus using the flash in dark environments. Is this > feature currently available on any of Pentax's DSLR's or is this now > superceded? > > Thanks PeterD > > > > > -- > 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. No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.339 / Virus Database: 270.12.37/2130 - Release Date: 05/23/09 07:00:00 -- 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: Pentax AF Lens + SF7 = DSLR
I almost want to change my filters for the next few days. But only almost. William Robb - Original Message - From: "Adam Maas" Subject: Re: Pentax AF Lens + SF7 = DSLR Actually, telephoto lenses don't provide any inherent result that can't be achieved also by reducing sensor size or subject distance. Longer lenses provide narrower Fields of View. Reducing sensor size achieves the same thing. That's because Field of View is conditional on both focal length and sensor format. Change either and the same effect is achieved. Magnification is a matter of focal length and focus distance but that's irrelevant to the equation in when it comes to anything except working distance for Macro and Depth of Field calculations (Since DoF actually depends on aperture and magnification, not focal length). Technically, a telephoto lens is merely a lens which has an optical centre further from the focal plane than the physical centre of the optical group. It's possible to have a telephoto wide-angle lens, although that's a much more rare occurance than the opposite (a retrofocus lens which is also a long lens, like the Olympus ZD 25 Pancake and ZD 35/3.5 Macro or the Pentax DA 35 Limited). -- 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: Pentax AF Lens + SF7 = DSLR
On Mon, May 25, 2009 at 11:01 PM, Bran Everseeking wrote: > On Mon, 25 May 2009 16:04:16 -0700 > Joseph McAllister wrote: > >> Telephoto lenses don't reach out, they narrow the usable field of >> view at the same time increasing resolution to render that field >> sharp. > > telephoto lenses do have a narrower FOV but the image on an aps > sensor/film with any lens is a crop of the image made with the same lens > on a 35mm sensor/film. thus the barrel in the centre of the image is > the same size... not larger as the implied 100=150 would have one > believe telephoto lenses provide magnification of distant views, reach. > > semantics are important if we are to understand one another. > > what you are saying does not match my understanding though may be only > different in dialect. > Actually, telephoto lenses don't provide any inherent result that can't be achieved also by reducing sensor size or subject distance. Longer lenses provide narrower Fields of View. Reducing sensor size achieves the same thing. That's because Field of View is conditional on both focal length and sensor format. Change either and the same effect is achieved. Magnification is a matter of focal length and focus distance but that's irrelevant to the equation in when it comes to anything except working distance for Macro and Depth of Field calculations (Since DoF actually depends on aperture and magnification, not focal length). Technically, a telephoto lens is merely a lens which has an optical centre further from the focal plane than the physical centre of the optical group. It's possible to have a telephoto wide-angle lens, although that's a much more rare occurance than the opposite (a retrofocus lens which is also a long lens, like the Olympus ZD 25 Pancake and ZD 35/3.5 Macro or the Pentax DA 35 Limited). -- 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: Pentax AF Lens + SF7 = DSLR
On Mon, 25 May 2009 16:04:16 -0700 Joseph McAllister wrote: > Telephoto lenses don't reach out, they narrow the usable field of > view at the same time increasing resolution to render that field > sharp. telephoto lenses do have a narrower FOV but the image on an aps sensor/film with any lens is a crop of the image made with the same lens on a 35mm sensor/film. thus the barrel in the centre of the image is the same size... not larger as the implied 100=150 would have one believe telephoto lenses provide magnification of distant views, reach. semantics are important if we are to understand one another. what you are saying does not match my understanding though may be only different in dialect. -- "Love" is that condition in which the happiness of another person is essential to your own... Jealousy is a disease, love is a healthy condition.- Robert Heinlein -- 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: Pentax AF Lens + SF7 = DSLR
On Tue, 26 May 2009 08:18:56 +1000 Brian Walters wrote: > Yes, I understand that. It's a peeve of mine too. I thought using > the qualifying term "equivalent to" correctly explained the > situation. Doesn't it? I guess equivalent and field of view were too far apart for my brain this afternoon -- "Love" is that condition in which the happiness of another person is essential to your own... Jealousy is a disease, love is a healthy condition.- Robert Heinlein -- 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: Pentax AF Lens + SF7 = DSLR
On May 25, 2009, at 09:31 , Bran Everseeking wrote: On Mon, 25 May 2009 16:01:59 +1000 Brian Walters wrote: The 35-70 will be equivalent to about 52-105 due to the sensor being smaller than 24mm x 36mm size of 35mm film. If you need wide angle, you will need a new lens. the 35-70 will still be a 35-70. no extra reach is created I know most know its a crop factor not a tele increase but it has become a pet peeve. I think the delusion is a selling point. Pet peeve or not, telephoto lenses are rated by their angle of view, ie: 2°, 7°, which is based on the receiving end, in this particular case, a 24 x 36 mm chunk o'film. IF you reduce the size of the receiver, ie: APS-C sensor, you have used a portion of the angle of acceptance (crop factor) and mathematically re-defined the lens's now usable angle of view by a factor of 0.666, or 2/3rds. We think of that as a 1.5x crop factor, when it in this case is a reduction in the angle of view we are using, effectively narrowing the field, and therefor increasing the telephoto filed of view properties by 1.5. Telephoto lenses don't reach out, they narrow the usable field of view at the same time increasing resolution to render that field sharp. Where is my logic (not so clearly constructed) wrong here? Or is this just all semantics? If it doesn’t excite you, This thing that you see, Why in the world, Would it excite me? —Jay Maisel Joseph McAllister pentax...@mac.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: Pentax AF Lens + SF7 = DSLR
On Mon, 25 May 2009 10:31 -0600, "Bran Everseeking" wrote: > On Mon, 25 May 2009 16:01:59 +1000 > Brian Walters wrote: > > > The 35-70 will be > > equivalent to about 52-105 due to the sensor being smaller than 24mm x > > 36mm size of 35mm film. If you need wide angle, you will need a new > > lens. > > the 35-70 will still be a 35-70. no extra reach is created Yes, I understand that. It's a peeve of mine too. I thought using the qualifying term "equivalent to" correctly explained the situation. Doesn't it? Cheers Brian ++ Brian Walters Western Sydney Australia http://members.westnet.com.au/brianwal/SL/ > I know most know its a crop factor not a tele increase but it has > become a pet peeve. I think the delusion is a selling point. > > -- -- -- http://www.fastmail.fm - Does exactly what it says on the tin -- 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: Pentax AF Lens + SF7 = DSLR
On Mon, 25 May 2009 16:01:59 +1000 Brian Walters wrote: > The 35-70 will be > equivalent to about 52-105 due to the sensor being smaller than 24mm x > 36mm size of 35mm film. If you need wide angle, you will need a new > lens. the 35-70 will still be a 35-70. no extra reach is created I know most know its a crop factor not a tele increase but it has become a pet peeve. I think the delusion is a selling point. -- "Love" is that condition in which the happiness of another person is essential to your own... Jealousy is a disease, love is a healthy condition.- Robert Heinlein -- 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: Pentax AF Lens + SF7 = DSLR
Thanks all for the "speedy" replies Nice to see the old lenses can still be utilized, this is a definite bonus to now being able to set more aside for a "Body Only" Pentax deal. Just find that my current Olympus C-730 UltraZoom 10x Optical is "slow" to respond to zoom and focus (by today's standards) and it was purchased as more of a "crossover" functionality between a P&S snapper to some fine telephoto capabilities, and has served me well. Thanks Peter D (Adelaide) John Coyle wrote: Peter, those lenses should work well, as others have already said. I have a Tokina 400/5.6 MF lens which is very good on digital. The K7 has a built-in focus assist light, and some of the Pentax flashes, such as the AF-330FTZ, will throw a low-intensity red beam to ensure accurate focus. HTH John in Brisbane -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Peter Sent: Monday, 25 May 2009 2:47 PM To: PDML@pdml.net Subject: Pentax AF Lens + SF7 = DSLR Have a Pentax SF7 (film) camera with a SMC Pentax-F Zoom 35-70 f3.5 AF) (Also have a Tokina 70-210 f4.5 AF) Are these lenses usable on any Pentax Digital SLR's? I am currently investigating at upgrading to Digital SLR. Am particularly interested in the new K-7 (still waiting for pricing in Australia) or the K-m. The feature I liked most about my old SF7 was the "AF spotbeam" which assisted with auto-focus using the flash in dark environments. Is this feature currently available on any of Pentax's DSLR's or is this now superceded? Thanks PeterD -- 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: Pentax AF Lens + SF7 = DSLR
Peter, those lenses should work well, as others have already said. I have a Tokina 400/5.6 MF lens which is very good on digital. The K7 has a built-in focus assist light, and some of the Pentax flashes, such as the AF-330FTZ, will throw a low-intensity red beam to ensure accurate focus. HTH John in Brisbane -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Peter Sent: Monday, 25 May 2009 2:47 PM To: PDML@pdml.net Subject: Pentax AF Lens + SF7 = DSLR Have a Pentax SF7 (film) camera with a SMC Pentax-F Zoom 35-70 f3.5 AF) (Also have a Tokina 70-210 f4.5 AF) Are these lenses usable on any Pentax Digital SLR's? I am currently investigating at upgrading to Digital SLR. Am particularly interested in the new K-7 (still waiting for pricing in Australia) or the K-m. The feature I liked most about my old SF7 was the "AF spotbeam" which assisted with auto-focus using the flash in dark environments. Is this feature currently available on any of Pentax's DSLR's or is this now superceded? Thanks PeterD -- 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: Pentax AF Lens + SF7 = DSLR
Hi Peter As others have said, those lenses will be fine on any Pentax DSLR with the proviso that the field of view will be different. The 35-70 will be equivalent to about 52-105 due to the sensor being smaller than 24mm x 36mm size of 35mm film. If you need wide angle, you will need a new lens. Cheers Brian ++ Brian Walters Western Sydney Australia http://members.westnet.com.au/brianwal/SL/ On Mon, 25 May 2009 14:16 +0930, "Peter" wrote: > Have a Pentax SF7 (film) camera with a SMC Pentax-F Zoom 35-70 f3.5 AF) > > (Also have a Tokina 70-210 f4.5 AF) > > Are these lenses usable on any Pentax Digital SLR's? I am currently > investigating at upgrading to Digital SLR. > > Am particularly interested in the new K-7 (still waiting for pricing in > Australia) or the K-m. > > The feature I liked most about my old SF7 was the "AF spotbeam" which > assisted with auto-focus using the flash in dark environments. Is this > feature currently available on any of Pentax's DSLR's or is this now > superceded? > > Thanks PeterD > > -- -- http://www.fastmail.fm - The way an email service should be -- 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: Pentax AF Lens + SF7 = DSLR
I've used the 35-70mm on my *ist-D and Ds cameras with good results. I haven't tried in on higher resolution sensors, but I expect that it will produce fine images. I can't tell you anything specific about the Tokina, but in general when you use a lens that covers the full 24x36mm frame of 35mm film are usually better on the APS-C sensor size associated with Pentax DSLRs. This is mainly due to the crop effect, a lot of lens corner and edge defects are simply not recorded. Peter wrote: Have a Pentax SF7 (film) camera with a SMC Pentax-F Zoom 35-70 f3.5 AF) (Also have a Tokina 70-210 f4.5 AF) Are these lenses usable on any Pentax Digital SLR's? I am currently investigating at upgrading to Digital SLR. Am particularly interested in the new K-7 (still waiting for pricing in Australia) or the K-m. The feature I liked most about my old SF7 was the "AF spotbeam" which assisted with auto-focus using the flash in dark environments. Is this feature currently available on any of Pentax's DSLR's or is this now superceded? Thanks PeterD -- -- The free man owns himself. He can damage himself with either eating or drinking; he can ruin himself with gambling. If he does he is certainly a damn fool, and he might possibly be a damned soul; but if he may not, he is not a free man any more than a dog. --G. K. Chesterton -- 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: Pentax AF Lens + SF7 = DSLR
Both those lenses will work with Pentax DSLRs. The K7 has a built in AF assist lamp, but all previous models use a pulse of light from the pop-up flash. Cheers, Dave (in Perth) > -Original Message- > From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of > Peter > Sent: Monday, 25 May 2009 12:47 PM > To: PDML@pdml.net > Subject: Pentax AF Lens + SF7 = DSLR > > Have a Pentax SF7 (film) camera with a SMC Pentax-F Zoom 35-70 f3.5 AF) > > (Also have a Tokina 70-210 f4.5 AF) > > Are these lenses usable on any Pentax Digital SLR's? I am currently > investigating at upgrading to Digital SLR. > > Am particularly interested in the new K-7 (still waiting for pricing in > Australia) or the K-m. > > The feature I liked most about my old SF7 was the "AF spotbeam" which > assisted with auto-focus using the flash in dark environments. Is this > feature currently available on any of Pentax's DSLR's or is this now > superceded? > > Thanks PeterD -- 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.
