PDA

View Full Version : Macro photography with and without macro lenses



cjj2003
25-Nov-2014, 11:35
Hello!

I'm attempting to do macro photography with a Sinar P, 210mm MC Sinaron-S lens and Leaf Aptus 22 back. I'm comparing the results to my Canon 5dMk2 and 180L macro lens. To my eye, the results are indistinguishable @ f/22 (no movements) in terms of sharpness, contrast, etc. Would a true macro lens improve the image from the Sinar/Leaf? I'm looking at a Rodenstock APO-macro or Nikkor Am at 210mm.

Keep in mind that the Canon and Leaf back have the same resolution but the Leaf has no AA filter, so I was expecting it to produce sharper results, at least at the pixel level.

Thanks in advance for your advice,
Chad

Dan Fromm
25-Nov-2014, 12:07
How close is macro, i.e., what magnification are you working at? The Leaf's sensor is larger, 48x36 mm, the Canon's is smaller, 24x36, i.e., half frame. Tell us more about the shots you're comparing and how you're measuring "sharpness."

cjj2003
25-Nov-2014, 12:19
Good point. At the moment I'm comparing images of a watch dial and judging sharpness by eye at 100-300% magnification in photoshop. The Canon is at slightly more than 1:1 magnification (with a short extension tube) and the Leaf is at slightly less than 1:1 magnification -- in such a way that the field of view is approximately the same (ie. the face of the watch roughly fills the frame on both so when I view them side by side at the same magnification in photoshop they are the same size).

Bob Salomon
25-Nov-2014, 12:44
To really see the difference you would use the macro digital lens not the analog one. For digital it is the 120 Apo Macro Sironar Digital. For film it would be the 120mm Apo Macro Sironar.

You would also see better digital results with a digital view camera like the M679cs or the Techno where the gearing is much more precise then the controls on an analog view camera.

Dan Fromm
25-Nov-2014, 13:40
Other things equal, if you shoot the Canon at higher magnification it will do a better job of separating fine details in the subject than the Leaf back will. Other things equal.

A watch dial isn't the best subject. You want a subject with fine details at a range of spacings so that you can estimate how well the lens/film (I know you're shooting digital) combination you're using separates fine details. Resolution is about separating fine detail. You also need fine detail all over the subject to see how well the lens/film combination does towards the edges of the field.

The Canon lens is probably best at around f/8 - f/11, that's how my manual focus MicroNikkors are. The Sinaron is probably best around f/22. And, as Bob suggested, a real macro lens for medium format has got to do better close up than the Sinaron, which is optimized for something like "far away."

cjj2003
25-Nov-2014, 13:42
Frankly, I don't understand how anyone can do macro photography with a 120mm lens. That means I have to be 12cm from my subject. Where do I put my lights!? But that's another topic...

I suppose my real question is, what is the real world difference between a regular lens and a dedicated macro lens? Ideally I'd love to see some side-by-side comparisons.

cjj2003
25-Nov-2014, 13:44
Yes, I thought f/22 would give a clear advantage to the leaf over the Canon, that's why I was surprised by the results. I agree I need a better test target.

Patrick13
25-Nov-2014, 14:25
Not sure where f22 falls in in that area where your chosen lens' diffraction overtakes the quality from stopping down a bit? You may be hiding the difference in fuzz. My 105mm macro seems optimal around 5.6 to 8, for example.

Also, you should add a flat subject like a stamp to your tests in addition to subjections with dimension to check against field curvature where a macro lens should be more flat up close.

PS: for macro, a ring light means never having to say I'm sorry. :rolleyes:

Bob Salomon
25-Nov-2014, 14:35
Yes, I thought f/22 would give a clear advantage to the leaf over the Canon, that's why I was surprised by the results. I agree I need a better test target.

The Canon has an image size of 24 x 36mm while the Leaf is a 645. To get the depth of field on a 35mm equal to the Leaf, with the same focal length lens you have to be stopped down further on the Canon. But at f22 on the Canon you will be in diffraction.

With a modern digital macro lens for the Leaf on your Sinar optimal aperture will be at f8 to 11. On your Sinar 45 with film optimal aperture will be at f22. On your Canon optimal aperture will be about 2 stops from wide open.

Then compare results.

Dan Fromm
25-Nov-2014, 15:02
Frankly, I don't understand how anyone can do macro photography with a 120mm lens. That means I have to be 12cm from my subject. Where do I put my lights!? But that's another topic...

I suppose my real question is, what is the real world difference between a regular lens and a dedicated macro lens? Ideally I'd love to see some side-by-side comparisons.

Not quite right. Lens' front node (usually located near the diaphragm) to subject distance = lens' focal length requires infinite magnification. In the range of magnifications you've told us about, front node to subject distance is around twice focal length.

Re diffraction and all that, you may be in trouble at marked f/22, effective (near 1:1) f/44. You'll certainly be in trouble at marked f/32, effective f/64.

cjj2003
25-Nov-2014, 16:50
Not quite right. Lens' front node (usually located near the diaphragm) to subject distance = lens' focal length requires infinite magnification. In the range of magnifications you've told us about, front node to subject distance is around twice focal length.

Re diffraction and all that, you may be in trouble at marked f/22, effective (near 1:1) f/44. You'll certainly be in trouble at marked f/32, effective f/64.


Oh, yes I was being careless; anyway, I prefer a longer telephoto for the macro work I do.

I've noticed diffraction tends to kick in around f/22 for the Leaf and f/16 for the Canon, but I didn't really mean to have a discussion comparing them. I'm really interested in comparing a macro and non-macro 210mm lens at macro distances.

Dan Fromm
25-Nov-2014, 17:20
I've never done the comparison you need. Where are you located? If you're in the right place you should be able to rent a 210 Schneider macro lens as recommended by Bob or a 210 Nikkor macro lens. Run your own trials and then you'll know which suits you better.

Another option is a process lens but opinions on whether they're sharp enough to use as taking lenses close up are very divided. I've shot a 55/8 Repro Claron against a number of other 50 mm or so macro lenses at magnifications above 1:1. The others included 40/4.5 Luminar, 45/4.5 Mikrotar, 50/3.5 Neupolar, 55/2.8 MicroNikkor (reversed), 63/4.5 Luminar, all lenses wide open and at one and two stops down. The Repro Claron didn't have a chance, at those magnifications diffraction is a killer and its maximum aperture was too small. I've also shot a 210/9 Konica Hexanon GR II against a 200/4 MicroNikkor AIS, both on a Nikon. At 1:2, the MicroNikkor's closest focusing distance on its own mount, the GR II was much better from f/9 to f/22.

Ken Lee
25-Nov-2014, 17:20
I'm really interested in comparing a macro and non-macro 210mm lens at macro distances.

Rodenstock made a 210mm Macro Sironar N lens. It is available on the used market in Copal 3 shutter and on Sinar DB board. In normal configuration, it is optimized for 1:3 to 1:1. Reversing the elements optimizes it for 1:1 to 3:1, which is macro distance. If I recall correctly, they offered a 300mm Macro in the same design, but have never seen one for sale.

Regular lenses are optimized for 1:10 or 1:20 and will do alright up to 1:1, but for real macro shooting there are real macro lenses.

Symmetrical process lenses optimized for 1:1 will also serve well since being symmetrical their corrections hold at all distances, but they open to f/9 and are thus harder to use under dim lighting. They have less usable coverage, although at close distance their coverage is considerable anyway.

NickyLai
25-Nov-2014, 19:13
...... That means I have to be 12cm from my subject. Where do I put my lights!? ........

There are some inexpensive fiber optic light, in the bay, that is good for very close lens to subject macro photography.

http://www.ebay.com/bhp/fiber-optic-illuminator

I got mine from there and use it as attach photography.

Bob Salomon
26-Nov-2014, 07:51
Rodenstock made a 210mm Macro Sironar N lens. It is available on the used market in Copal 3 shutter and on Sinar DB board. In normal configuration, it is optimized for 1:3 to 1:1. Reversing the elements optimizes it for 1:1 to 3:1, which is macro distance. If I recall correctly, they offered a 300mm Macro in the same design, but have never seen one for sale.

Regular lenses are optimized for 1:10 or 1:20 and will do alright up to 1:1, but for real macro shooting there are real macro lenses.

Symmetrical process lenses optimized for 1:1 will also serve well since being symmetrical their corrections hold at all distances, but they open to f/9 and are thus harder to use under dim lighting. They have less usable coverage, although at close distance their coverage is considerable anyway.

Rodenstock made two Makro lenses, the 210 and the 300 that worked as Ken described. The vast majority were supplied in Copal shutter and quite a few were also supplied in Prontor Professional 3 and Sinar shutters. They were used on all brands of view cameras and the least expensive way to buy one would be in Copal 3 unless you will use it on a Sinar with the shutter. If you buy one in Sinar DB and do not have the Sinar shutter then you will also need to buy a Copal 3 shutter for it plus a set of aperture scales.

The lenses did operate as Ken said, by reversing the elements as you get to 1:1 and beyond. At 1:1 you can leave the elements in either configuration.

These two lenses were discontinued by Rodenstock several years ago and wer replaced with the 120 and the 180mm Apo Macro Sironar lenses. These were optimized from 1:5 to 2:1 and the elements did not get reversed. These lenses have since been supplemented with the 120 Apo Macro Sironar Digital with a smaller circle, higher correction and a larger optimal f stop.

The 180 was in a 1 and both 120s are in a 0 shutter. The 180mm fully covered 810 at 1:1 and the 120 covered 810 at 2:1. The digital 120 Macro will not come close to covering 810.

The above lenses are far bettewr performers then a process lens when shooting 3-dimensional items at macro ranges. Especially if the detail is required up to the edges of the frame. Also the macro lenses will perform optimally over a range of f stops where the process lenses will be optimal at their design aperture of f 22 for lenses shorter then 600mm.

Dan Fromm
26-Nov-2014, 09:35
Bob, I agree with you except on two points.

The optimal aperture for a process lens depends on magnification. For example, the recommended copy format for the 250/9 Apo Ronar CL is 10" x 12" at 1:1. Rodenstock recommends using f/22 with that format and magnifications. This because performance at the edges of the image circle, corners of the image, is very important and the off-axis aberrations that are affected by relative aperture aren't under good enough control at larger apertures. So you're absolutely right in recommending that people who want to use a 240 Apo Ronar to copy 10 x 12 to 10 x 12 should shoot at f/22.

But if the OP is shooting tiny format -- 24 x 36 or 36 x 48 -- at magnifications around 1:1. For him the far off-axis aberrations that are important for the lens' intended use don't matter. All of the better grade of repro lenses that I've tested are worse centrally at f/22 than at f/16, some, dialyte type Apo Nikkors in particular, are worse centrally at f/16 than at f/11. So your advice isn't really correct for the OP.

The other point on which we differ is on how helpful field curvature is when shooting 3-D subjects. In principle, field curvature that conformed to the subject's lack of flatness would be helpful. In practice subjects come in many shapes, some irregular, and a lens' curvature of field is what it is. Lenses are designed, ideally, to have no field curvature, not all make it. The idea that process lenses, which usually have very little field curvature, are unsuited to shooting anything that isn't perfectly flat is a canard.

Cheers,

Dan

cjj2003
26-Nov-2014, 09:57
I'm surprised that there is very little information comparing macro to non-macro lenses for macro use. Even Rodenstock's own literature is not very informative. For example, this document: http://www.rodenstock-photo.com/Archiv/e_Rodenstock_Analog_Lenses_27-42__8226.pdf has mtf curves for both the apo-sironar-S and Apo-Macro-Sironar but as far as I can tell, the two curves are very similar and they have no information about focus distance.

Bob Salomon
26-Nov-2014, 10:14
Bob, I agree with you except on two points.

The optimal aperture for a process lens depends on magnification. For example, the recommended copy format for the 250/9 Apo Ronar CL is 10" x 12" at 1:1. Rodenstock recommends using f/22 with that format and magnifications. This because performance at the edges of the image circle, corners of the image, is very important and the off-axis aberrations that are affected by relative aperture aren't under good enough control at larger apertures. So you're absolutely right in recommending that people who want to use a 240 Apo Ronar to copy 10 x 12 to 10 x 12 should shoot at f/22.

But if the OP is shooting tiny format -- 24 x 36 or 36 x 48 -- at magnifications around 1:1. For him the far off-axis aberrations that are important for the lens' intended use don't matter. All of the better grade of repro lenses that I've tested are worse centrally at f/22 than at f/16, some, dialyte type Apo Nikkors in particular, are worse centrally at f/16 than at f/11. So your advice isn't really correct for the OP.

The other point on which we differ is on how helpful field curvature is when shooting 3-D subjects. In principle, field curvature that conformed to the subject's lack of flatness would be helpful. In practice subjects come in many shapes, some irregular, and a lens' curvature of field is what it is. Lenses are designed, ideally, to have no field curvature, not all make it. The idea that process lenses, which usually have very little field curvature, are unsuited to shooting anything that isn't perfectly flat is a canard.

Cheers,

Dan

Dan,

In the good old days when catalog studios shot film a large department store in the mid west bought an old supermarket and converted it into what was then called a "Super Studio". Everything was shot on view cameras and they had ordered, through their dealer, everything that had an effect on color specially balanced and matched at the factory. Things like light boxes, flash equipment and from us, a large array of Apo Ronar lenses.

As they were getting fully into production the powers that be (art directors) were not all that happy with the jewelry shots, especially. They spread the jewelry out on the product tables in such a way that in one shot they could use multiple different high detail shots that were all taken at one time. This meant that they had product filling the frame, edge to edge, corner to corner and the diamond ring in the upper corner had to be just as sharp and crisp as the saphire ring in the bottom opposite corner and they both had to be as sharp, detailed and crisp as the pearl necklace in the center. And process lenses just could not do this. Neither could general purpose 1:10 and 1:20 corrected lenses. But Makro Sironar lenses had absolutely no problem handling the nuances of the fine jewelry detail and roundness.

I had to spend a few days with them as they were getting everything nailed down but it certainly was a learning experience for all of us. Studion managers, photographers, art directors, the dealer and me. Process lenses simply can not match the macro lenses from edge to edge and corner to corner when dealing with a 3 dimensional object. But they do a hell of a job when copying maps and documents!

Ken Lee
26-Nov-2014, 10:15
as far as I can tell, the two curves are very similar and they have no information about focus distance.

In that document, focus distance is conveyed as "scale".

For the normal lens, the scale is 0.1x or 1/10 or 1:10. For the macro lens, the scale is 0.5x or 5/10 or 1:2

That the two curves are similar in spite of difference in scale is an argument in favor of the quality of the macro lens at close distance.

Bob Salomon
26-Nov-2014, 10:25
I'm surprised that there is very little information comparing macro to non-macro lenses for macro use. Even Rodenstock's own literature is not very informative. For example, this document: http://www.rodenstock-photo.com/Archiv/e_Rodenstock_Analog_Lenses_27-42__8226.pdf has mtf curves for both the apo-sironar-S and Apo-Macro-Sironar but as far as I can tell, the two curves are very similar and they have no information about focus distance.
I think that you are misreading them. They are at different ratios. The MTF for the macro is at 0.5x and the fall off, distortion and color aberration curves are also, depending on the curve, at ratios of 0.5x or 0.2 to 2.0x.

The Apo Sironar S curves are at 0.1x for MTF and fall-off and color aberration and 0.03 to 0.2x for distortion.

cjj2003
26-Nov-2014, 11:03
In that document, focus distance is conveyed as "scale".

For the normal lens, the scale is 0.1x or 1/10 or 1:10. For the macro lens, the scale is 0.5x or 5/10 or 1:2

That the two curves are similar in spite of difference in scale is an argument in favor of the quality of the macro lens at close distance.

Thank you! That certainly helps though I don't think you can necessarily draw that conclusion. I would like to see a comparison of the two lenses at the same scale.

Michael Graves
26-Nov-2014, 11:10
I don't know if this works with large format lenses or not. But several years ago, I took on an assignment to photograph a gentleman's stamp collection. A colleague told me to buy a simple reversing ring for my 50mm and then mount it on a regular bellows. The difference between the reversed lens and the normally mounted lens at the same ratio (appx: 2:1 if I recall correctly) was readily apparent.

cjj2003
26-Nov-2014, 11:19
But if the OP is shooting tiny format -- 24 x 36 or 36 x 48 -- at magnifications around 1:1. For him the far off-axis aberrations that are important for the lens' intended use don't matter. All of the better grade of repro lenses that I've tested are worse centrally at f/22 than at f/16, some, dialyte type Apo Nikkors in particular, are worse centrally at f/16 than at f/11. So your advice isn't really correct for the OP.

I think this gets to what I'm really interested in: will a dedicated macro lens make any difference for my intended use? I suspect that the MTF of the macro and non-macro lenses are the same in the central 48x36mm region at macro scale. However, I suspect that I may see an improvement when I use tilts and swings.

Dan Fromm
26-Nov-2014, 11:21
Michael, taking and enlarging lenses are optimized for a small negative behind the lens and a large subject/print in front of it. When you shoot a taking lens above 1:1 or use an enlarging lens to make a reduction (in both cases, large negative behind the lens, small subject/print in front of it) you're throwing away the lens' optimizations. That's why we reverse lenses when shooting above 1:1/making reductions. The exception is lenses that are perfectly symmetrical, such as dialyte type Apo Nikkors and Apo Saphirs.

That's why you got better results at 2:1 with a reversed 50 mm lens than at 2:1 with it mounted normally.

Dan Fromm
26-Nov-2014, 11:24
Dan,

In the good old days when catalog studios shot film a large department store in the mid west bought an old supermarket and converted it into what was then called a "Super Studio". Everything was shot on view cameras and they had ordered, through their dealer, everything that had an effect on color specially balanced and matched at the factory. Things like light boxes, flash equipment and from us, a large array of Apo Ronar lenses.

As they were getting fully into production the powers that be (art directors) were not all that happy with the jewelry shots, especially. They spread the jewelry out on the product tables in such a way that in one shot they could use multiple different high detail shots that were all taken at one time. This meant that they had product filling the frame, edge to edge, corner to corner and the diamond ring in the upper corner had to be just as sharp and crisp as the saphire ring in the bottom opposite corner and they both had to be as sharp, detailed and crisp as the pearl necklace in the center. And process lenses just could not do this. Neither could general purpose 1:10 and 1:20 corrected lenses. But Makro Sironar lenses had absolutely no problem handling the nuances of the fine jewelry detail and roundness.

I had to spend a few days with them as they were getting everything nailed down but it certainly was a learning experience for all of us. Studion managers, photographers, art directors, the dealer and me. Process lenses simply can not match the macro lenses from edge to edge and corner to corner when dealing with a 3 dimensional object. But they do a hell of a job when copying maps and documents!

Bob, thanks for the story. Do you recall the magnification and aperture(s) they photographer(s) worked at?

cjj2003
26-Nov-2014, 11:26
I don't think it's possible to reverse my lens; I unscrewed the the front and rear cells from the shutter but they have different diameters. I could put the shutter on the wrong side of the lensboard but then I would have some trouble firing the shutter as it would be INSIDE the camera!

Bob Salomon
26-Nov-2014, 11:55
Bob, thanks for the story. Do you recall the magnification and aperture(s) they photographer(s) worked at?

Not any longer. This was back when the Makro 210 and 300 were first out. And that has been a while ago!

Bob Salomon
26-Nov-2014, 12:00
Thank you! That certainly helps though I don't think you can necessarily draw that conclusion. I would like to see a comparison of the two lenses at the same scale.

Then you are getting to the point where you should investigate renting a macro and its closest non-macro equivelent and shooting what you want to shoot with the lighting you want to use and on the medium that you plan to use and compare the results. If you tell us where you are located we may be able to refer you to some dealers that rent those kinds of lenses.

Michael Graves
26-Nov-2014, 12:04
Michael, taking and enlarging lenses are optimized for a small negative behind the lens and a large subject/print in front of it. When you shoot a taking lens above 1:1 or use an enlarging lens to make a reduction (in both cases, large negative behind the lens, small subject/print in front of it) you're throwing away the lens' optimizations. That's why we reverse lenses when shooting above 1:1/making reductions. The exception is lenses that are perfectly symmetrical, such as dialyte type Apo Nikkors and Apo Saphirs.

That's why you got better results at 2:1 with a reversed 50 mm lens than at 2:1 with it mounted normally.

So that would not work for large format then? I've never taken on another assignment of that nature, so my experience is limited to that one time.

cjj2003
26-Nov-2014, 12:18
Then you are getting to the point where you should investigate renting a macro and its closest non-macro equivelent and shooting what you want to shoot with the lighting you want to use and on the medium that you plan to use and compare the results. If you tell us where you are located we may be able to refer you to some dealers that rent those kinds of lenses.

Yeah it's a good idea. Fotocare has (more or less) what I want. I live in NYC so there are plenty of options.

Dan Fromm
26-Nov-2014, 12:20
So that would not work for large format then? I've never taken on another assignment of that nature, so my experience is limited to that one time.

Exactly. This is true for nearly all lenses. The exceptions are, as I already said, perfectly symmetrical lenses and lenses designed to be used only above 1:1, e.g., Luminars, Photars, ...

cjj, the trick for reversing lenses in #1 shutters on a view camera is to screw a reversing ring into the lens' front filter threads and then use a retaining ring or flange to hold it on the lens board. In your case, you must be using bellows or extension tubes to get the magnification, you'll need an adapter that will screw into the lens' front cell's filter threads and attach to y'r bellows or tube or whatever.

cjj2003
26-Nov-2014, 12:28
cjj, the trick for reversing lenses in #1 shutters on a view camera is to screw a reversing ring into the lens' front filter threads and then use a retaining ring or flange to hold it on the lens board. In your case, you must be using bellows or extension tubes to get the magnification, you'll need an adapter that will screw into the lens' front cell's filter threads and attach to y'r bellows or tube or whatever.

I'm not using anything special beyond the regular camera bellows. Maybe I'm misunderstanding what's being reversed; I thought it should be the order of the cells, ie. the rear cell goes to the front and points forward and the front cell goes in the rear and points backwards.

Dan Fromm
26-Nov-2014, 14:10
I'm not using anything special beyond the regular camera bellows. Maybe I'm misunderstanding what's being reversed; I thought it should be the order of the cells, ie. the rear cell goes to the front and points forward and the front cell goes in the rear and points backwards.

Hmm. What's the difference between what you describe and simply turning the whole lens-shutter assembly around? That's what I tried to describe.

Jim Jones
26-Nov-2014, 17:21
I'm not using anything special beyond the regular camera bellows. Maybe I'm misunderstanding what's being reversed; I thought it should be the order of the cells, ie. the rear cell goes to the front and points forward and the front cell goes in the rear and points backwards.

Lens and shutter should be reversed as a unit, unless the diaphragm is centered between the front and rear ends of the shutter. A diaphragm that is incorrectly positioned can greatly affect optical performance.

Dan Fromm
26-Nov-2014, 18:04
Lens and shutter should be reversed as a unit, unless the diaphragm is centered between the front and rear ends of the shutter. A diaphragm that is incorrectly positioned can greatly affect optical performance.

Jim, are you sure?

Lenses in #1 shutters can't be reversed by swapping the cells around because the tube diameters front and rear are different but lenses in #0s can be.

#0 cock-and-shoots are nearly symmetrical, the diaphragm is 10.2 mm from the front of a 20 mm tube. #0 press shutters aren't quite that symmetrical, front of tube to diaphragm is 11.7 mm. See http://www.skgrimes.com/products/new-copal-shutters.

The difference's usual practical significance is that lenses whose rear cells go deep into the tube sometimes interfere with #0 press shutters diaphragms. Same goes for #1 press shutters. Been there, got in trouble with both sizes. But not with reversed lenses in a #0 press.

Cheers,

Dan

cjj2003
28-Nov-2014, 13:17
Thanks for all of your comments and advice. I just bought a Nikkor AM 210mm lens, I'll do a side-by-side comparison and post the results here when it arrives.

EdSawyer
28-Nov-2014, 17:46
Great lens, great choice, IMNSHO, the best of the LF macro lenses.

cjj2003
7-Dec-2014, 09:51
Just to wrap this up, here is the result of my testing: I'm comparing the Rodenstock 210mm Sinaron S (non macro lens) against the Nikkor AM * ED 210mm (macro lens) at approximately 1:1 magnification. What I discovered is that at the center of the image the two lenses are identical at f/22. If tilt movements are added, the lenses are still identical at f/22. However, at larger apertures the Rodenstok really falls apart while the Nikkor remains very sharp. The bellow image compares an image of a diamond. Tilt is 20 degrees on the front standard and 20 degrees on the rear standard. At f/22 I see no difference. At f/16 the Nikkor is slightly better while at f/11 the Rodenstock is very soft and the Nikkor remains sharp. This result is moderately disappointing to me since I shoot macro photography pretty much always at f/22 and smaller apertures.


126171

You can take a look at the full resolution image on flickr:
https://farm9.staticflickr.com/8595/15348596233_825e66b4b9_o.jpg

8x10 user
7-Dec-2014, 10:53
The F//11 Rodenstock image appears the be out of focus.

When I'm shooting MFD with my 120mm Macro Sinaron Digital I try not to stop down past F/16. F/11 would be a better choice in terms of sharpness but sometimes I need more DOF. The trade off between aperture, diffraction, and DOF is much more of an issue with macro photography. Often a higher resolution back will not produce more details. I do know of some high end commercial macro photographers who use higher resolution backs but they use Hasselblad and focus stack in "Phocus".

A shorter focal length lens will give you a bit more DOF at the same aperture, 80-120mm is common for medium format.

Non macro lens with ED glass such as the Apo-Sironar-S should do a little better then non macro lenses without ED glass such as the Apo Sironar N. Enlarging lenses are surprisingly good for image taking with digital backs. Duplication lenses will work for macro work. In fact it is said that the sharpest macro lens is a high end duplication lens that Nikon developed for optical duplication of movie film.

"Digital" macro lenses are great and I suspect that regular macro lenses will also work well at normal working apertures.

Dan Fromm
7-Dec-2014, 11:04
A shorter focal length lens will give you a bit more DOF at the same aperture, 80-120mm is common for medium format.Not at the same magnification.

Ken Lee
7-Dec-2014, 11:46
I see a slight improvement with the Nikkor macro lens even at f/22.

How about off-center ? I should think we'd find greater differences as we reach the limits of coverage, rather than at the center where quality is optimal.

Also, at 1:1 what aperture makes these lenses diffraction-limited, where any comparison is of questionable utility ?

Since you're testing a macro lens, how about 2:1 or greater magnification ? Wouldn't the difference become even more evident by then ?

cjj2003
7-Dec-2014, 12:07
I see a slight improvement with the Nikkor macro lens even at f/22.

How about off-center ? I should think we'd find greater differences as we reach the limits of coverage, rather than at the center where quality is optimal.

Also, at 1:1 what aperture makes these lenses diffraction-limited, where any comparison is of questionable utility ?

Since you're testing a macro lens, how about 2:1 or greater magnification ? Wouldn't the difference become even more evident by then ?

These are all good points. Since I was using so much tilt, I sort of thought that I was testing the edge of the lens. The diffraction limit for this lens and digital sensor (Leaf Aptus 22) is around f/22 which is why I didn't test at smaller apertures.


The F//11 Rodenstock image appears the be out of focus.

It is very much in focus -- the quality is just really poor.

cjj2003
7-Dec-2014, 12:23
Technically, the diffraction limit is around f/11 because the effective f stop has increased by two stops at 1:1 magnification! However, based on my observations, I think diffraction doesn't become a major issue until somewhere between f/32 and f/22 for this setup.

8x10 user
7-Dec-2014, 12:41
The diffraction limit for this lens and digital sensor (Leaf Aptus 22) is around f/22 which is why I didn't test at smaller apertures.


Not at 1:1...

At 1:1 F/22 becomes F/44, the diffraction limit (http://www.kenrockwell.com/tech/diffraction.htm) for F/45 is 35 line pairs per mm... 35 x 2 x 25.4 =1778 lines per inch

The sensor size for a 22 MP MFD cameras is 9 microns or ~2800 lines per inch (very close to the best results possible with chrome film and large format cameras, per inch)

However the images do not look that bad because the camera already uses interpolation to combine pixels from the bayer grid. In addition camera software is pretty good at sharpening images that are not quite tack sharp at 100%.

With my Sinar 54H (22mp multishot), I can see an improvement to the areas in focus (at 100%), when I use a slightly wider aperture then f/22. Although I often have to reduce my resolution 50% for many uses so the difference is often not noticeable.

With the F/11 rodenstock image I dont see an area infront of the plane of focus so its hard to tell. I do think the 210mm AM picture is focused to a slight farther away point in the image.

8x10 user
7-Dec-2014, 12:42
You beat me to it.


Technically, the diffraction limit is around f/11 because the effective f stop has increased by two stops at 1:1 magnification! However, based on my observations, I think diffraction doesn't become a major issue until somewhere between f/32 and f/22 for this setup.

8x10 user
7-Dec-2014, 12:44
The Apo Ronar is said to be diffraction limited at F/22. It would be interesting to see how one compares to the AMED at smaller apertures.