Re: A Question About Macro Lenses
I only own older extension only macros; from what I gather from reading, zoomy zoom macros suffer no light falloff when close-focusing but may lose a bit of focal length. Sounds like a good trade-off to me. -Lon Rob Studdert wrote: I find using macro lenses at non-macro distances most often more advantageous than not. I see (and test) no optical deficit for one (over regular lenses of comparable quality, FL and speed) and secondly I only have to lug a single lens for the FL to cover a multitude of shooting situations. I'd still like to see indisputable proof of just how inferior my zoomy zoom zoom type macros are over the old fixed lens designed macros in normal shooting situations.
Re: A Question About Macro Lenses
On 15 Nov 2004 at 6:25, Lon Williamson wrote: I only own older extension only macros; from what I gather from reading, zoomy zoom macros suffer no light falloff when close-focusing but may lose a bit of focal length. Sounds like a good trade-off to me. I'd say that's a pretty accurate assumption WRT FL, my V125/2.5 looks to be just a tad over 100mm FL when approaching 1:1 mag. However in a recent little test I made comparing my V to an older bellows lens the V seemed to need about a half stop extra exposure a any aperture to equal the old lens exposure wise. Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
RE: A Question About Macro Lenses
On 15 Nov 2004 at 7:23, J. C. O'Connell wrote: Unless the 125mm zoomed out to 62.5mm at 1:1, it is going to need exposure compensation. Of course you are correct, I was simply drawing a relative comparison to another lens. What you have is essentially a variable aperture zoom with that lens, how do do you know what exposure compensations to use? I don't really care but I do know now that relative to a non-zoom macro lens it requires about an extra half stop when approaching 1:1. I haven't used external meters for macro photography since the late 80's. Then I had a 67 and bellows and I was glad to get my hands on a TTL prism. Does the lens barrel have exposure compensation markings on it? No At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work... ..or you (I) could use the TTL metering, which I do quite successfully. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
RE: A Question About Macro Lenses
Unless the 125mm zoomed out to 62.5mm at 1:1, it is going to need exposure compensation. What you have is essentially a variable aperture zoom with that lens, how do do you know what exposure compensations to use? Does the lens barrel have exposure compensation markings on it? At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work... JCO -Original Message- From: Rob Studdert [mailto:[EMAIL PROTECTED] Sent: Monday, November 15, 2004 7:31 AM To: [EMAIL PROTECTED] Subject: Re: A Question About Macro Lenses On 15 Nov 2004 at 6:25, Lon Williamson wrote: I only own older extension only macros; from what I gather from reading, zoomy zoom macros suffer no light falloff when close-focusing but may lose a bit of focal length. Sounds like a good trade-off to me. I'd say that's a pretty accurate assumption WRT FL, my V125/2.5 looks to be just a tad over 100mm FL when approaching 1:1 mag. However in a recent little test I made comparing my V to an older bellows lens the V seemed to need about a half stop extra exposure a any aperture to equal the old lens exposure wise. Cheers, Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
RE: A Question About Macro Lenses
TTL is fine but a lot of people do Macro with strobes (myself included), and I am not aware of any SLR cameras that can do TTL flash metering. My technique is I use a flash meter, calculate bellows factor exposure compensation, and determine a base fstop. But even then I usually bracket unless I have used exact same lighting setup, film speed, lens and magnification, etc. I would imagine with a DSLR its just a matter of running a few exposures and adjust fstop until you get what you want on the image review screen. JCO -Original Message- From: Rob Studdert [mailto:[EMAIL PROTECTED] Sent: Monday, November 15, 2004 8:46 AM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses On 15 Nov 2004 at 7:23, J. C. O'Connell wrote: Unless the 125mm zoomed out to 62.5mm at 1:1, it is going to need exposure compensation. Of course you are correct, I was simply drawing a relative comparison to another lens. What you have is essentially a variable aperture zoom with that lens, how do do you know what exposure compensations to use? I don't really care but I do know now that relative to a non-zoom macro lens it requires about an extra half stop when approaching 1:1. I haven't used external meters for macro photography since the late 80's. Then I had a 67 and bellows and I was glad to get my hands on a TTL prism. Does the lens barrel have exposure compensation markings on it? No At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work... ..or you (I) could use the TTL metering, which I do quite successfully. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
RE: A Question About Macro Lenses
On Mon, 15 Nov 2004, J. C. O'Connell wrote: What you have is essentially a variable aperture zoom with that lens, how do do you know what exposure compensations to use? You don't, TTL calculates things for you. Kostas
Re: A Question About Macro Lenses
Most SLR cameras made in the last 25 years or so can do TTL flash metering. The LX does it quite nicely. When checking exposures with a DSLR, you don't want to rely on the image review. It can be very misleading. You really have to look at the histogram. On Nov 15, 2004, at 8:30 AM, J. C. O'Connell wrote: TTL is fine but a lot of people do Macro with strobes (myself included), and I am not aware of any SLR cameras that can do TTL flash metering. My technique is I use a flash meter, calculate bellows factor exposure compensation, and determine a base fstop. But even then I usually bracket unless I have used exact same lighting setup, film speed, lens and magnification, etc. I would imagine with a DSLR its just a matter of running a few exposures and adjust fstop until you get what you want on the image review screen. JCO -Original Message- From: Rob Studdert [mailto:[EMAIL PROTECTED] Sent: Monday, November 15, 2004 8:46 AM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses On 15 Nov 2004 at 7:23, J. C. O'Connell wrote: Unless the 125mm zoomed out to 62.5mm at 1:1, it is going to need exposure compensation. Of course you are correct, I was simply drawing a relative comparison to another lens. What you have is essentially a variable aperture zoom with that lens, how do do you know what exposure compensations to use? I don't really care but I do know now that relative to a non-zoom macro lens it requires about an extra half stop when approaching 1:1. I haven't used external meters for macro photography since the late 80's. Then I had a 67 and bellows and I was glad to get my hands on a TTL prism. Does the lens barrel have exposure compensation markings on it? No At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work... ..or you (I) could use the TTL metering, which I do quite successfully. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
RE: A Question About Macro Lenses
On Mon, 15 Nov 2004, J. C. O'Connell wrote: TTL is fine but a lot of people do Macro with strobes (myself included), and I am not aware of any SLR cameras that can do TTL flash metering. I probably don't understand what you mean by TTL flash metering. All Pentax AF, the Super-A and the LX do TTL flash metering during exposure (off the film/sensor). They quench the flash. I guess the strobes are not controllable like that or sth? Kostas
Re: A Question About Macro Lenses
- Original Message - From: J. C. O'Connell Subject: RE: A Question About Macro Lenses At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work... Your question applies to when ttl flash control is not available, such as when using studio strobes. Since all my cameras have a built in meter, I use the continuous light meter to render an accurate assessment of the required exposure compensation by measuring how many stops of light I lose when extending the lens from infinity to the focus point. William Robb
RE: A Question About Macro Lenses
See my last post, TTL Auto Flash is not same as TTL flash meteringAnd yes I would think most studio type strobes do not interface with the camera even if you wanted to do TTL AUTO flash... JCO -Original Message- From: Kostas Kavoussanakis [mailto:[EMAIL PROTECTED] Sent: Monday, November 15, 2004 8:42 AM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses On Mon, 15 Nov 2004, J. C. O'Connell wrote: TTL is fine but a lot of people do Macro with strobes (myself included), and I am not aware of any SLR cameras that can do TTL flash metering. I probably don't understand what you mean by TTL flash metering. All Pentax AF, the Super-A and the LX do TTL flash metering during exposure (off the film/sensor). They quench the flash. I guess the strobes are not controllable like that or sth? Kostas
RE: A Question About Macro Lenses
TTL flash metering is not the same a TLL AUTO FLASH. TTL flash metering gives you the correct fstop value to use with a fixed (usually maximum output) flash power. TTL Auto flash on the other hand uses a fixed fstop and adjusts the flash power DOWN to match that fstop via TTL. Not the same and not as good when you need maximum light JCO -Original Message- From: Paul Stenquist [mailto:[EMAIL PROTECTED] Sent: Monday, November 15, 2004 8:41 AM To: [EMAIL PROTECTED] Subject: Re: A Question About Macro Lenses Most SLR cameras made in the last 25 years or so can do TTL flash metering. The LX does it quite nicely. When checking exposures with a DSLR, you don't want to rely on the image review. It can be very misleading. You really have to look at the histogram. On Nov 15, 2004, at 8:30 AM, J. C. O'Connell wrote: TTL is fine but a lot of people do Macro with strobes (myself included), and I am not aware of any SLR cameras that can do TTL flash metering. My technique is I use a flash meter, calculate bellows factor exposure compensation, and determine a base fstop. But even then I usually bracket unless I have used exact same lighting setup, film speed, lens and magnification, etc. I would imagine with a DSLR its just a matter of running a few exposures and adjust fstop until you get what you want on the image review screen. JCO -Original Message- From: Rob Studdert [mailto:[EMAIL PROTECTED] Sent: Monday, November 15, 2004 8:46 AM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses On 15 Nov 2004 at 7:23, J. C. O'Connell wrote: Unless the 125mm zoomed out to 62.5mm at 1:1, it is going to need exposure compensation. Of course you are correct, I was simply drawing a relative comparison to another lens. What you have is essentially a variable aperture zoom with that lens, how do do you know what exposure compensations to use? I don't really care but I do know now that relative to a non-zoom macro lens it requires about an extra half stop when approaching 1:1. I haven't used external meters for macro photography since the late 80's. Then I had a 67 and bellows and I was glad to get my hands on a TTL prism. Does the lens barrel have exposure compensation markings on it? No At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work... ..or you (I) could use the TTL metering, which I do quite successfully. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: A Question About Macro Lenses
- Original Message - From: J. C. O'Connell Subject: RE: A Question About Macro Lenses As for indisputable proof, my burden isnt any greater than yours and is based on the simple concept that lenses that do less can do what little they do better that lenses that do more (prime vs zoom concept). T Concepts are good. Physical evidence has credibility. William Robb
Re: A Question About Macro Lenses
Shel Belinkoff stopped playing with his cameras long enough to write: The macro gods have been very, very good to me, and I have a couple of fine Pentax lenses. While preparing to do a close-up of a three dimensional object the thought crossed my mind that a macro lens is best suited for flat objects, like stamps and documents, rather than something with greater depth like the small toy car I was photographing. Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. So, what do the macro and close-up gurus have to say about this? Under what circumstances would a macro lens be the better choice, and when might an ordinary lens be a better option? I don't claim to be a guru but I am an enthusiast. The major difference between the macro lenses and the non-macro lenses is that the macro lenses allow you to focus a lot closer. If you're far enough away from your subject that both lenses can focus then I wouldn't expect to see an appreciable difference in the images at f/8 or f/11. It might make for an interesting experiment. Tom Reese
Re: A Question About Macro Lenses
The major difference between the macro lenses and the non-macro lenses is that the macro lenses allow you to focus a lot closer. Agreed. For most of us (who usually would be shooting small and/or close-up 3-dimensional objects, and not just pieces of paper, for example), I suspect that the flat-field characteristic of a macro lens would be less important than the close-focusing ability. If you're far enough away from your subject that both lenses can focus then I wouldn't expect to see an appreciable difference in the images at f/8 or f/11. I would agree. The K 105/2.8 is a pretty sharp lens and the A 100/2.8 Macro certainly is, and their focal lengths are almost the same (so that their depths of field should be very close). Even at f/2.8 or f/4, I would think that the differences would not be large. Fred
Re: A Question About Macro Lenses
Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. Under what circumstances would a macro lens be the better choice, and when might an ordinary lens be a better option? I really like the A 100/2.8 Macro a lot (one of my favorite lenses). I also used to own the K 105/2.8 (at the same time as I owned the A 100/2.8 Macro). I pack the 100/2.8 Macro for almost any outing, whereas I almost never packed the K 105/2.8. The 100/2.8 Macro let me shoot almost anything that I wanted (using a lens in the 100-ish range), close or far, while the K lens could not focus too close. The maximum apertures were the same. Bokeh (important to me) may not be the best feature of the 100/2.8 Macro, but it certainly is not for the 105/2.8, either. So, in answer to your question, Shel, specifically referring to these two lenses, I'd say that - for me - the A 100/2.8 Macro would ~always~ be the better choice - g. Fred
RE: A Question About Macro Lenses
I don't agree (1): The major differences between macro lenses and non-macro lenses is that macro lenses have special optical designs which optimize near field usage in the range of 1:1 to 1:10 (approx). They have different OPTICAL designs. It is not just a matter of close focus capability, that can be achieved by putting non-macro lenses on tubes or bellows but they will not perform nearly as well a true macro lenses because just increasing close focus ability without the optical redesign yields mediocre results. I don't agree (2): Weve been over this a zillion times, focal length does not directly affect DOF, magnification does. If you use a 100mm or a 105mm at the same magnification (slightly further working distance with the 105mm) the relative DOF will be the same with the 105mm as the 100mm using same aperture setting. JCO -Original Message- From: Fred [mailto:[EMAIL PROTECTED] Sent: Saturday, November 13, 2004 9:20 AM To: Tom Reese Subject: Re: A Question About Macro Lenses The major difference between the macro lenses and the non-macro lenses is that the macro lenses allow you to focus a lot closer. Agreed. For most of us (who usually would be shooting small and/or close-up 3-dimensional objects, and not just pieces of paper, for example), I suspect that the flat-field characteristic of a macro lens would be less important than the close-focusing ability. If you're far enough away from your subject that both lenses can focus then I wouldn't expect to see an appreciable difference in the images at f/8 or f/11. I would agree. The K 105/2.8 is a pretty sharp lens and the A 100/2.8 Macro certainly is, and their focal lengths are almost the same (so that their depths of field should be very close). Even at f/2.8 or f/4, I would think that the differences would not be large. Fred
RE: A Question About Macro Lenses
In the close up range shorter than what the 105 mm normally focuses to (i.e. resorting to put tubes on the 105mm) I would expect the 100mm Macro to absolutely crush the 105 performance. BUT, when used at the optimum working distance of the 105mm (I do not know the figure, 10 meters ? ) I would bet that the 100mm would have a hard time matching the performance of the 105 because the 100 is one of those pseudo zooms with many more elements than necessary for a general purpose application like the 105 is designed forThis has also been argued about a zillion times too. It is the prime vs zoom debate (sort of) and if you use a prime at its ideal conditons, they are usually pretty hard to match with a (pseudo)zoom at those same ( ideal for the prime) conditons... JCO -Original Message- From: Fred [mailto:[EMAIL PROTECTED] Sent: Saturday, November 13, 2004 9:30 AM To: [EMAIL PROTECTED] Subject: Re: A Question About Macro Lenses Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. Under what circumstances would a macro lens be the better choice, and when might an ordinary lens be a better option? I really like the A 100/2.8 Macro a lot (one of my favorite lenses). I also used to own the K 105/2.8 (at the same time as I owned the A 100/2.8 Macro). I pack the 100/2.8 Macro for almost any outing, whereas I almost never packed the K 105/2.8. The 100/2.8 Macro let me shoot almost anything that I wanted (using a lens in the 100-ish range), close or far, while the K lens could not focus too close. The maximum apertures were the same. Bokeh (important to me) may not be the best feature of the 100/2.8 Macro, but it certainly is not for the 105/2.8, either. So, in answer to your question, Shel, specifically referring to these two lenses, I'd say that - for me - the A 100/2.8 Macro would ~always~ be the better choice - g. Fred
RE: A Question About Macro Lenses
Try it yourself and then comment. I've done it and the differences don't seem to be that great - hardly noticeable at all in some situations, not at all in others. Camera was mounted on a Pentax macro copy stand, same camera used, same film, and a refconverter used @ 2X to check focusing accuracy. While there may be some differences that become obvious at some point, they were not obvious in a 5x7 print. I don't think the 100/2.8 macro in any way crushed the K105/2.8 when the subject was a three dimensional object. Results may be substantially different when photographing a two dimensional object. Shel [Original Message] From: J. C. O'Connell [EMAIL PROTECTED] In the close up range shorter than what the 105 mm normally focuses to (i.e. resorting to put tubes on the 105mm) I would expect the 100mm Macro to absolutely crush the 105 performance.
RE: A Question About Macro Lenses
what magnification? if just under the minimum focus distance of the 105mm lens it might be too bad but there is going to be more and more differences as you get closer and closer. A lot of lenses have their minimum focus distance not because it wasn't easily possible to make the focus mount extend more, they have their minimum focus distance because the image quality falls off and they do not want to design the lens to cover that range with a minimum level of quality up to their standards JCO -Original Message- From: Shel Belinkoff [mailto:[EMAIL PROTECTED] Sent: Saturday, November 13, 2004 10:34 AM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses Try it yourself and then comment. I've done it and the differences don't seem to be that great - hardly noticeable at all in some situations, not at all in others. Camera was mounted on a Pentax macro copy stand, same camera used, same film, and a refconverter used @ 2X to check focusing accuracy. While there may be some differences that become obvious at some point, they were not obvious in a 5x7 print. I don't think the 100/2.8 macro in any way crushed the K105/2.8 when the subject was a three dimensional object. Results may be substantially different when photographing a two dimensional object. Shel [Original Message] From: J. C. O'Connell [EMAIL PROTECTED] In the close up range shorter than what the 105 mm normally focuses to (i.e. resorting to put tubes on the 105mm) I would expect the 100mm Macro to absolutely crush the 105 performance.
Re: A Question About Macro Lenses
i bet, the differences at 3x5 print wouldn't have been obvious either. best, mishka On Sat, 13 Nov 2004 07:33:46 -0800, Shel Belinkoff [EMAIL PROTECTED] wrote: ... While there may be some differences that become obvious at some point, they were not obvious in a 5x7 print. I don't think the 100/2.8 macro in any way crushed the K105/2.8 when the subject was a three dimensional object. Results may be substantially different when photographing a two dimensional object. Shel
Re: A Question About Macro Lenses
I don't agree Thanks for your disagreements, JCO - g. Fred
Re: A Question About Macro Lenses
And the point of your erudite comment is? Shel [Original Message] From: Mishka [EMAIL PROTECTED] To: [EMAIL PROTECTED] Date: 11/13/2004 8:04:37 AM Subject: Re: A Question About Macro Lenses i bet, the differences at 3x5 print wouldn't have been obvious either. best, mishka On Sat, 13 Nov 2004 07:33:46 -0800, Shel Belinkoff [EMAIL PROTECTED] wrote: ... While there may be some differences that become obvious at some point, they were not obvious in a 5x7 print. I don't think the 100/2.8 macro in any way crushed the K105/2.8 when the subject was a three dimensional object. Results may be substantially different when photographing a two dimensional object. Shel
RE: A Question About Macro Lenses
J. C. O'Connell objected to my opinion and responded: I don't agree (1): The major differences between macro lenses and non-macro lenses is that macro lenses have special optical designs which optimize near field usage in the range of 1:1 to 1:10 (approx). They have different OPTICAL designs. It is not just a matter of close focus capability, that can be achieved by putting non-macro lenses on tubes or bellows but they will not perform nearly as well a true macro lenses because just increasing close focus ability without the optical redesign yields mediocre results. I am well aware that the optical designs are very different but in real world actual usage, the major difference is that the macro lenses focus closer. At f/8 or f/11 both lenses are at optimal resolution and I don't think you'll see an appreciable difference in image quality when both lenses can focus on the subject. If the 105mm lens required an extension tube to focus on the subject then the macro lens would probably outperform it. Refer to the original question. The images were shot at a distance where both lenses were able to focus on the subject. At that distance, the macro lens did not yield a substantially better image than the 105. I am not at all surprised that it did not. Tom Reese
RE: A Question About Macro Lenses
There is ZERO advantage to using macro lenses at subject distances covered by normal lenses. Actully there is usually a disadvantage, so using a macro lens for non macro work makes no sense and my comments were certainly not for that case! JCO -Original Message- From: Tom Reese [mailto:[EMAIL PROTECTED] Sent: Saturday, November 13, 2004 12:00 PM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses J. C. O'Connell objected to my opinion and responded: I don't agree (1): The major differences between macro lenses and non-macro lenses is that macro lenses have special optical designs which optimize near field usage in the range of 1:1 to 1:10 (approx). They have different OPTICAL designs. It is not just a matter of close focus capability, that can be achieved by putting non-macro lenses on tubes or bellows but they will not perform nearly as well a true macro lenses because just increasing close focus ability without the optical redesign yields mediocre results. I am well aware that the optical designs are very different but in real world actual usage, the major difference is that the macro lenses focus closer. At f/8 or f/11 both lenses are at optimal resolution and I don't think you'll see an appreciable difference in image quality when both lenses can focus on the subject. If the 105mm lens required an extension tube to focus on the subject then the macro lens would probably outperform it. Refer to the original question. The images were shot at a distance where both lenses were able to focus on the subject. At that distance, the macro lens did not yield a substantially better image than the 105. I am not at all surprised that it did not. Tom Reese
Re: A Question About Macro Lenses
the point is that your comment that i quoted was pointless. mishka On Sat, 13 Nov 2004 08:17:35 -0800, Shel Belinkoff [EMAIL PROTECTED] wrote: And the point of your erudite comment is? Shel From: Mishka [EMAIL PROTECTED] i bet, the differences at 3x5 print wouldn't have been obvious either. [EMAIL PROTECTED] wrote: While there may be some differences that become obvious at some point, they were not obvious in a 5x7 print. I don't think the 100/2.8 macro in any way crushed the K105/2.8 when the subject was a three dimensional object.
RE: A Question About Macro Lenses
Hi Shel, Yesterday I was in the Camera World store here in Oregon, and they gave me a free cd from Photoflex about lighting. I'm looking for studio/strobe lights. The CD-ROM was very helpful. They have numerous samples and one them showed how they photographed a minature car. It is very detailed with regards to digital set up, ie white balance, etc. But it also goes thru their selection of f-stops, lights, shutter speed, etc. that shows how the photo changes with each change. The minature car sample was interesting as they were able to make it look like a real car. Might be of some value to you, and it is free. I would think you would find it at any reasonbly-sized photo store. Have a good one... --- J. C. O'Connell [EMAIL PROTECTED] wrote: There is ZERO advantage to using macro lenses at subject distances covered by normal lenses. Actully there is usually a disadvantage, so using a macro lens for non macro work makes no sense and my comments were certainly not for that case! JCO -Original Message- From: Tom Reese [mailto:[EMAIL PROTECTED] Sent: Saturday, November 13, 2004 12:00 PM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses J. C. O'Connell objected to my opinion and responded: I don't agree (1): The major differences between macro lenses and non-macro lenses is that macro lenses have special optical designs which optimize near field usage in the range of 1:1 to 1:10 (approx). They have different OPTICAL designs. It is not just a matter of close focus capability, that can be achieved by putting non-macro lenses on tubes or bellows but they will not perform nearly as well a true macro lenses because just increasing close focus ability without the optical redesign yields mediocre results. I am well aware that the optical designs are very different but in real world actual usage, the major difference is that the macro lenses focus closer. At f/8 or f/11 both lenses are at optimal resolution and I don't think you'll see an appreciable difference in image quality when both lenses can focus on the subject. If the 105mm lens required an extension tube to focus on the subject then the macro lens would probably outperform it. Refer to the original question. The images were shot at a distance where both lenses were able to focus on the subject. At that distance, the macro lens did not yield a substantially better image than the 105. I am not at all surprised that it did not. Tom Reese __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
Re: A Question About Macro Lenses
And why was my comment pointless? the point is that your comment that i quoted was pointless.
RE: A Question About Macro Lenses
I don't know the magnification. Both lenses were used so that the object filled the frame to the same degree. Shel [Original Message] From: J. C. O'Connell [EMAIL PROTECTED] To: [EMAIL PROTECTED] Date: 11/13/2004 7:54:40 AM Subject: RE: A Question About Macro Lenses what magnification? if just under the minimum focus distance of the 105mm lens it might be too bad but there is going to be more and more differences as you get closer and closer.
Re: A Question About Macro Lenses
you went like Try it yourself and then comment. I've done it and the differences don't seem to be that great - hardly noticeable at all in some situations, not at all in others -- and then revealed that this outburst (pretty arrogant, if you ask me) is based on 5x enlargement (35mm - 5x7). my point was, that if you use even smaller enlargement, the differences between pretty much all lenses would be negligible, and this try it yourself and then comment part was completely pointless, since you haven't tried to do a meaningful comparison yourself. cheers, mishka On Sat, 13 Nov 2004 10:13:32 -0800, Shel Belinkoff [EMAIL PROTECTED] wrote: And why was my comment pointless? the point is that your comment that i quoted was pointless.
Re: A Question About Macro Lenses
- Original Message - From: Mishka Subject: Re: A Question About Macro Lenses since you haven't tried to do a meaningful comparison yourself. And what would be a meaningful comparison then? William Robb
Re: A Question About Macro Lenses
- Original Message - From: Shel Belinkoff Subject: RE: A Question About Macro Lenses Try it yourself and then comment. I've done it and the differences don't seem to be that great - hardly noticeable at all in some situations, not at all in others. Camera was mounted on a Pentax macro copy stand, same camera used, same film, and a refconverter used @ 2X to check focusing accuracy. While there may be some differences that become obvious at some point, they were not obvious in a 5x7 print. I don't think the 100/2.8 macro in any way crushed the K105/2.8 when the subject was a three dimensional object. Results may be substantially different when photographing a two dimensional object. I had a small product job to do a while back that required about a 1/2 life size reproduction, but because of limitations on where I could set up, I ended up using the M150/3.5 on a tube, rather than the A100/2.8 macro. In this application, the resulting chromes were just fine. Presuming that you can't put a non macro lens onto a tube and shooting excellent quality close ups is a mistake. Right now my slide copy rig is incorporating the 77mm lens, as it is the only focal length I have that I am able to make work with the istD and get full frame reproduction of the slide, using bellows and duplicator. So far, I haven't seen any optical problems with this rig either. Reproduction ratio would be about 2/3 life size, I expect. William Robb
Re: A Question About Macro Lenses
- Original Message - From: Tom Reese Subject: RE: A Question About Macro Lenses At f/8 or f/11 both lenses are at optimal resolution and I don't think you'll see an appreciable difference in image quality when both lenses can focus on the subject. Depends on the size of the swimming pool, doesn't it? William Robb
Re: A Question About Macro Lenses
Mishka Mumbled: you went like Try it yourself and then comment. I've done it and the differences don't seem to be that great - hardly noticeable at all in some situations, not at all in others -- and then revealed that this outburst (pretty arrogant, if you ask me) is based on a 5x enlargement (35mm - 5x7). Arrogant? I actually used the two lenses in question, was specific about the enlargement size, stated that the difference didn't SEEM to be that great, that in some situations were hardly noticeable (not UNnoticable). IOW, I offered a point of reference while JCO has not done any comparison at all, but, rather, made his statement based on some theoretical concept. Sure, a 5x7 doesn't tell all there is, and a much larger magnification may be more revealing of small differences. However, I used what I had, observed that there were some differences (which anyone familiar with photography would know to be magnified with greater enlargement), posted my observations, and noted exactly how the comparison was made. I did not do a scientific test, but I did do a real world comparison. Real world being that the comparison was done using a size print that was suitable and appropriate to the purpose it was intended. If you paid attention to my original post, I was not stating that I knew best, or that what I've done was anything more than a jumping off point to ASK A QUESTION. I was trying to get more information and open up the topic for further discussion so we all might, you know, like learn something. my point was, that if you use even smaller enlargement, the differences between pretty much all lenses would be negligible, and this try it yourself and then comment part was completely pointless, since you haven't tried to do a meaningful comparison yourself. What would a meaningful comparison be? To suggest that JCO try it himself is not pointless. Maybe he would come up with a conclusion and derive some information that would help us even further wrt to which lens might be better for photographing a 3D object rather than a flat object. The point here is simple: those that have not tried something, or made even the most basic comparison, have nothing, really, to say. Like, Cheers Shel
RE: A Question About Macro Lenses
On 13 Nov 2004 at 12:33, J. C. O'Connell wrote: There is ZERO advantage to using macro lenses at subject distances covered by normal lenses. Actully there is usually a disadvantage, so using a macro lens for non macro work makes no sense and my comments were certainly not for that case! I find using macro lenses at non-macro distances most often more advantageous than not. I see (and test) no optical deficit for one (over regular lenses of comparable quality, FL and speed) and secondly I only have to lug a single lens for the FL to cover a multitude of shooting situations. I'd still like to see indisputable proof of just how inferior my zoomy zoom zoom type macros are over the old fixed lens designed macros in normal shooting situations. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: A Question About Macro Lenses
- Original Message - From: Rob Studdert Subject: RE: A Question About Macro Lenses I find using macro lenses at non-macro distances most often more advantageous than not. I see (and test) no optical deficit for one (over regular lenses of comparable quality, FL and speed) and secondly I only have to lug a single lens for the FL to cover a multitude of shooting situations. I'd still like to see indisputable proof of just how inferior my zoomy zoom zoom type macros are over the old fixed lens designed macros in normal shooting situations. Are they inferior though? I don't think so. The whole idea of FREE was to correct chromatic aberation across the entire focus range. Trying the lens, finding that it is flawed, and writing it off because the flaw isn't acceptable to what you do is rational. Calling the thing a zoom because a side effect of the optical design is an apparent change of focal length, and then writing off the lens because you don't like zooms is pretty bogus. Or should I say: irrational. William Robb
RE: A Question About Macro Lenses
this is a worn out argument. Not all macro lenses are the same type of design. Every macro lens pentax made for example prior to the A series are poor performers at infinity and large apertures because the designers choose to optimize close range magnificaitons which is logical. Stopped down they are pretty good but not as good as general purpose lenses at long distances... As for indisputable proof, my burden isnt any greater than yours and is based on the simple concept that lenses that do less can do what little they do better that lenses that do more (prime vs zoom concept). T JCO -Original Message- From: Rob Studdert [mailto:[EMAIL PROTECTED] Sent: Saturday, November 13, 2004 7:32 PM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses On 13 Nov 2004 at 12:33, J. C. O'Connell wrote: There is ZERO advantage to using macro lenses at subject distances covered by normal lenses. Actully there is usually a disadvantage, so using a macro lens for non macro work makes no sense and my comments were certainly not for that case! I find using macro lenses at non-macro distances most often more advantageous than not. I see (and test) no optical deficit for one (over regular lenses of comparable quality, FL and speed) and secondly I only have to lug a single lens for the FL to cover a multitude of shooting situations. I'd still like to see indisputable proof of just how inferior my zoomy zoom zoom type macros are over the old fixed lens designed macros in normal shooting situations. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: A Question About Macro Lenses
Shel, I've done butterflies with a pair of LX's, one with the A100/2.8 Macro and one with the M100/2.8 and an extension tube. The results were quite satisfactory with the M100/2.8 and the tube, but not up to the quality of the A100/2.8 Macro. The extra detail was visible on the Macro's slides. Regards, Bob S. On Sat, 13 Nov 2004 08:41:07 -0500, Tom Reese [EMAIL PROTECTED] wrote: Shel Belinkoff stopped playing with his cameras long enough to write: The macro gods have been very, very good to me, and I have a couple of fine Pentax lenses. While preparing to do a close-up of a three dimensional object the thought crossed my mind that a macro lens is best suited for flat objects, like stamps and documents, rather than something with greater depth like the small toy car I was photographing. Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. So, what do the macro and close-up gurus have to say about this? Under what circumstances would a macro lens be the better choice, and when might an ordinary lens be a better option? I don't claim to be a guru but I am an enthusiast. The major difference between the macro lenses and the non-macro lenses is that the macro lenses allow you to focus a lot closer. If you're far enough away from your subject that both lenses can focus then I wouldn't expect to see an appreciable difference in the images at f/8 or f/11. It might make for an interesting experiment. Tom Reese
Re: A Question About Macro Lenses
While preparing to do a close-up of a three dimensional object the thought crossed my mind that a macro lens is best suited for flat objects, like stamps and documents, rather than something with greater depth like the small toy car I was photographing. Well, my take on this would be that a macro lens is designed to render flat objects well, because it is designed to have a flat field of focus, but this is not to say that it can't render 3-dimensional objects just fine. Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. Well, the depth of field of the two lenses, at matching apertures, would have to be very, very much the same. Fred
Re: A Question About Macro Lenses
i vaguely remember a discussion here some time ago, and i believe the consensus was that macro lenses are optimized for close distances, whereas normal lenses -- for infinity (or near-infinity, for macro purposes) flatness of field is also an issue. best, mishka On Fri, 12 Nov 2004 18:30:13 -0800, Shel Belinkoff [EMAIL PROTECTED] wrote: The macro gods have been very, very good to me, and I have a couple of fine Pentax lenses. While preparing to do a close-up of a three dimensional object the thought crossed my mind that a macro lens is best suited for flat objects, like stamps and documents, rather than something with greater depth like the small toy car I was photographing. Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. So, what do the macro and close-up gurus have to say about this? Under what circumstances would a macro lens be the better choice, and when might an ordinary lens be a better option? Shel
Re: A Question About Macro Lenses
On 12 Nov 2004 at 18:30, Shel Belinkoff wrote: The macro gods have been very, very good to me, and I have a couple of fine Pentax lenses. While preparing to do a close-up of a three dimensional object the thought crossed my mind that a macro lens is best suited for flat objects, like stamps and documents, rather than something with greater depth like the small toy car I was photographing. Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. Aside from their obvious benefits macros lenses are only best suited to photographing flat objects as they focus over a flat field, most non-macro lenses actually exhibit a semi-spherical plane of focus. I'd rather be using a macro lens than a standard lens if lighting permits for regular shooting as they generally render a more natural image. This is why you see so many images from me using my Voigtländer 125/2.5 and my A50/2.8 Macro, they are both great performers in most any shooting situation. Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998
Re: A Question About Macro Lenses
The zone of sharp focus is also extremely narrow at macro distances, even shooting with f22 or f32! This is why flat field shooting is also easier. The 'depth' or 'width' of the zone of sharp focus may only be 2 or 3 mm at the most. Cheers Shaun Mishka wrote: i vaguely remember a discussion here some time ago, and i believe the consensus was that macro lenses are optimized for close distances, whereas normal lenses -- for infinity (or near-infinity, for macro purposes) flatness of field is also an issue. best, mishka On Fri, 12 Nov 2004 18:30:13 -0800, Shel Belinkoff [EMAIL PROTECTED] wrote: The macro gods have been very, very good to me, and I have a couple of fine Pentax lenses. While preparing to do a close-up of a three dimensional object the thought crossed my mind that a macro lens is best suited for flat objects, like stamps and documents, rather than something with greater depth like the small toy car I was photographing. Using the A100/2.8 macro and the K105/2.8 on the same subject, there didn't seem to be any observable difference between the two photos. So, what do the macro and close-up gurus have to say about this? Under what circumstances would a macro lens be the better choice, and when might an ordinary lens be a better option? Shel -- _ Dr. Shaun Canning P.O. Box 21, Dampier, WA, 6714, Australia. m: 0400 204536 http://www.heritageservices.com.au [EMAIL PROTECTED] _
Re: A Question About Macro Lenses
The zone of sharp focus is also extremely narrow at macro distances, even shooting with f22 or f32! This is why flat field shooting is also easier. The 'depth' or 'width' of the zone of sharp focus may only be 2 or 3 mm at the most. Agreed. Click on the four macro shots, for f/4, f/8, f/16, and f/32, at the bottom of http://plg.komkon.org/a200_4m/a200_4m.html . Fred
