Ideal Macro Lens Advice

[cmoore]

Hello all,

What an amazing resource these forums are. I've spent many hours looking through the forums so I hope I haven't missed this being specifically dealt with elsewhere. I'm photographing small, flat objects about the size of a postage stamp on a Sinar P. The object is kept about 2 - 3 mm from the background. The background is a textured paper and appears in the frame. Obviously, I would like the object to be as sharp as possible but I also want the texture of the background paper to be defined.

Now, working at approximately 10:1 I know that the depth of field will be very small. The first time I did this, I used a 150mm f5.6 Sinaron reverse mounted. Shot at f22 I got acceptable depth of field but overall the image is quite soft. I've also used a 80mm nikkor enlarger lens. Reverse mounted again, shot at f22 again and the object is noticeably sharper but the background paper is softer - apparently less depth of field.

My question is this: at this magnification of approx 10:1 and hoping for 3mm depth of field, am I best off with a macro lens (reversed/not reversed), a reversed enlarger lens or a reversed copy lens? (all shots will be black and white)

Or am I chasing something that can't be done? Am I just toast?

Thanks in advance for any advice!

Cheers

Casey

[Mark Woods]

Hello Casey,

What are you focusing on? If it's the small object, you're wasting part of your DOF on the air in front of your object. The way DOF works, is whatever you focus on, 1/3 in front and 2/3 behind is in "focus." This depends on Circle of Confusion, size of enlargement, etc. On the Sinar P, the focus scale puts you in the middle (if I remember correctly). Look at the image focus & the BG and shoot a test with the focus set a little less than 1/3 behind the FG object.

Hope this helps.

[Jim Michael]

You could set a small reticle at a 45 degree angle and determine what setting provides acceptable dof.

If you end up scanning the negatives would focus stacking be a solution?

[Jeffrey Sipress]

Macro lenses are optimized for 1:1 reproduction. At 10:1 I have no idea about performance!

[Joshua Dunn]

Casey,

I have shot with a Nikkor 120mm AM on a Sinar system but never at 10:1. It’s a fabulous Macro lens and can usually be found priced quite reasonably. I doubt if you can get 10:1 out of it. Any Marco lens is going to be sharper than enlarging lenses or using lenses with the cells reversed. Schneider and Rodenstock have made 180mm Macro lenses and all three have made a 210mm Macro lenses. Sadly I have never shot with one.

If quality is of real concern get a good Macro lens. It sounds like you need a 210mm Macro lens to pull off what you are trying to accomplish, however if you can make a 180mm work it would help with the depth of field you are looking for. What Mark said is right regarding depth of field, as well as making sure the lens plane is square (meaning at the exact same angle) as the item being photographed. Either one of these will yield you better depth of field.

Does anyone near you rent large format lenses? I did a quick Google search and found Tempe Camera (http://www.tempecamera.biz/default.asp) (I know nothing about this company and have never used them) that rents a 210mm Macro Sironar-N (http://www.tempecamera.biz/210mm_f5_6_Macro_Sironar_N_Copal_3_p/rnt1626.htm) (Rodenstock). Maybe you should rent one first before investing in one. Or just rent it as needed if you only need it a couple of times a year. Most businesses that rent equipment will ship it as well if they are not near enough to you to pick up.

Hope this helps.

-Joshua

[Dan Fromm]

Hello Casey,

What are you focusing on? If it's the small object, you're wasting part of your DOF on the air in front of your object. The way DOF works, is whatever you focus on, 1/3 in front and 2/3 behind is in "focus." This depends on Circle of Confusion, size of enlargement, etc. On the Sinar P, the focus scale puts you in the middle (if I remember correctly). Look at the image focus & the BG and shoot a test with the focus set a little less than 1/3 behind the FG object.

Hope this helps.Mark, that's the conventional wisdom for shooting at moderate distances.

It is wrong for distant subjects, where more than all -- that's what infinite means -- of the DoF is behind the subject and for closeup, where DoF is symmetrical about the subject. If you don't believe me, do the arithmetic and then test it by shooting.

[Dan Fromm]

Casey, you want a lens designed for photomacrography and optimized for around 10:1. These lenses are diffraction-limited wide open and stopping them down only decreases DoF.

Candidate lenses include 25/2.5 Photar, 35/4.5 or 65/4.5 Macro Nikkor, 25/3.5 or 40/3.5 Luminar. All of these are designed to be used with front facing the subject. If you want relatively inexpensive and easy-to-find, a reversed 55/2.8 MicroNikkor shot at f/4 or a 25/1.9 Cine Ektar II reversed and shot at f/2.8 are competitive with the others. Given unlimited budget, I'd use the 25/2.5 Photar. Given limited budget, I'd probably take my 25/3.5 Luminar out of the drawer.

If you want reasonable image quality in the background, place the stamp closer than 3 mm to it. You'll have to experiment a little to find the distance that gives results that please you.

You may want to read the macro lens section of my lens diary. It is at http://www.galerie-photo.com/1-lens-6x9-dan-fromm.html (English) and http://www.galerie-photo.com/1-optiques-6x9-dan-fromm.html (French).

Something -- I've never understood what -- about closeup work makes people stupid and elicits flagrantly bad advice. There are good books on the subject whose authors understand closeup technique very well. Here are two that I own and recommend:

Bracegirdle, Brian. 1995. Scientific PhotoMACROgraphy. Bios Scientific Publishers. Oxford. 105 pp. ISBN 1 872748 49 X

Lefkowitz, Lester. 1979. The Manual of Close-Up Photography. Amphoto. Garden City, NY. 272 pp. ISBN 0-8174-2456-3 (hardbound) and 0-8174-2130-0 (softbound).

Bracegirdle is more specific about lenses than Lefkowitz. Buy both. They're focused on your problem.

[cmoore]

Hi guys,

Thanks for the input. I'm not scanning these negs but printing them myself about 33"x27" in the darkroom so small improvements will make a big impact on the final image.

I understand that macro lenses vary but that most are optimised for somewhere between 1:4 and 4:1. At 10:1 the logical thing to do would seem to be use an enlarger lens reversed. My object is near enough the same size as a 35mm neg and I want to get that image on to a 5x4 sheet of film. Or perhaps a copy lens would be the way to go?

Does depth of field increase with increase in focal length? This would seem logical as the subject to lens distance increases, so does the depth of field. So using a 80mm lens I only needed about 14" of bellows but had just 6 inches between subject and lens. Using 150mm I needed more like 30" of bellows but the subject was about 12" from the lens.

Due to their design, which of the 3 (macro, enlarger, copy) types of lenses will minimise diffraction at this magnification, or is design irrelevant and simply a function of bellows extension/focal length.

Thanks again.

Casey

[cmoore]

Thanks very much Dan, just seen your post after writing mine. I have ordered Lester Lefkowitz's book but wasn't aware of the other. I'll get my hands on that one too. Will read your diary and do some research into those lenses you recommend.

[Justin Cormack]

Depth of field only depends on magnification not focal length so the only solution is to move the background closer or to change its texture to look better defined.

[cmoore]

NIKON MACRO NIKKOR 35MM F4.5 8X-20X MAGNIFICATION 4"X5

Hi Dan, I just spotted this lens on Ebay which sounds ideal except for the working distances of around 14mm. I'm going to need 5 inches or more to be able to play with the light and shadow that the object throws on the background. So working within this limitation (enough object to lens distance) logic tells me that a reversed enlarger lens, in the 135mm - 180mm range should work well. I am essentially asking it to do the same as it would be within an enlarger - i.e. make a 4x5 enlargement from an object about the size of a 35mm neg.

Does that make sense or am I missing something? Does reversing the enlarger lens bring performance (sharpness) problems with it? I am not concerned with shutters as my exposures are 5 seconds or more and taking the lens board off to stop the lens down is no issue as my object doesn't move.

[pdmoylan]

Justin is absolutely correct regarding DOF as it relates to magnification. You have the same DOF with any focal length lens at the same magnification. Advertisements that WAs have greater DOF is a function of less magnification than telephotos.

Therefore as long as OP is getting sharp results with a reversed enlarger lens, a different lens will not matter in respect of DOF. Another option is to use less magnification and crop the final print. It might improve DOF slightly.

[Dan Fromm]

NIKON MACRO NIKKOR 35MM F4.5 8X-20X MAGNIFICATION 4"X5

Hi Dan, I just spotted this lens on Ebay which sounds ideal except for the working distances of around 14mm. I'm going to need 5 inches or more to be able to play with the light and shadow that the object throws on the background. So working within this limitation (enough object to lens distance) logic tells me that a reversed enlarger lens, in the 135mm - 180mm range should work well. I am essentially asking it to do the same as it would be within an enlarger - i.e. make a 4x5 enlargement from an object about the size of a 35mm neg.

Does that make sense or am I missing something? Does reversing the enlarger lens bring performance (sharpness) problems with it? I am not concerned with shutters as my exposures are 5 seconds or more and taking the lens board off to stop the lens down is no issue as my object doesn't move.

Casey, I think the listing is mistaken. At infinite magnification -- same situation as "subject at infinity," but turned around -- front node to subject distance is focal length. The 35 Macro Nikkor may lose a little working distance because the front node is probably close to the diaphragm, but still and all ... Fine lens, by the way, but out of my price range. The BIN price seems very high.

Conventional lighting techniques aren't the best for closeup. Learn more about closeup technique before deciding how to proceed. Wait for your copy of Lefkowitz to arrive. FWIW, I use light sources very close to the subject. When using a borrowed -- I go to it -- Wild Photomakroscope, fiber optic; with my own gear, electronic flash. Key rule is that a small point source near the subject behaves much like a large source far from it.

Reversing an enlarging lens will work and enlarging lenses come in a wide range of focal lengths. Remember, an enlarging lens is designed to have a large print in front of it and a small negative behind it. We reverse an enlarging lens when using it to shoot a large negative of a small subject in order to preserve its corrections. I suggested a couple of decent high performance macro lenses instead of a reversed enlarging lens because enlarging lenses aren't as well corrected as proper high performance macro lenses. In addition, enlarging lenses are usually slower and aren't best wide open so their best can't be as good.

If you can get the extension focal length doesn't matter. But getting to 10:1 with a 180 mm lens requires 1980 mm of extension; this is a problem for most of us. That's why the rule seems to be, the higher the magnification the shorter the lens.

One of the problems with discussions of photomacrography is that what seem like simple questions usually want book-length answers. Accept it and wait for the books to come. Another problem is that the simple photographic truths we live by when shooting at distance ain't so closeup. People naturally reason from what they're familiar with; unfortunately reasoning from shooting at normal distances to closeup doesn't work well.

Cheers,

Dan

[cmoore]

Thanks again to everyone. Dan, thank you for the detailed response. I will certainly be deep in to the text books when they arrive.

Regarding the reversed enlarger lens vs high performance macro lens, what corrections am I benefiting from with the macro lens? The subject is flat and I'm guessing that is what enlarger lenses are good at. Also, at 10:1 would even the macro lens benefit from being reversed?

[Dan Fromm]

The macro lenses I suggested are made to be used facing forwards, i.e., face plate towards the subject and mounting threads towards the film. I suggested one reversed cine lens and one reversed MicroNikkor; both need to be reversed when used above 1:1.

Enlarging lenses are abundant and, even new, aren't that expensive. "Real" macro lenses are scarce and were quite expensive when new. They commanded and still command higher prices than enlarging lenses that appear to be functionally equivalent.
This isn't due to crazy collectors, it is because a real macro lens gives better results than a reversed enlarging lens.

When you read my lens diary, you'll find that I use 4"/5.6 Enlarging Pro Raptar for closeup (< 1:1) and low magnification photomacrography (> 1:1), up to around 2:1, which is the highest it will go on a 2x3 Graphic. It is an exceptional lens. I've tried other enlarging lenses for those applications, don't use 'em. They're not good enough.

If you start looking for macro lenses, you'll find that Photars and Luminars command much higher prices than the equivalent B&L MicroTessars and MP-4 Tominons. They're better. A good 35/4.5 Tominon isn't a bad lens but a 40/4.5 Luminar is much better. And so on.

If you have an enlarging lens that will give you the magnification you want with the extension your camera will give, by all means try it out. Trying is cheap.

When you read my diary you'll see that I've tried things a sensible person wouldn't have. And y'know something? Sensible folks are sometimes right. In the realm you're trying to enter, sensible folks prefer real macro lenses.

Cheers ,

Dan

[cmoore]

Thanks to all who contributed. I have purchased a 120mm f5.6 Rodenstock Apo Macro Sironar. Lester Lefkowitz's book is on it's way and I have a lot of fun and hard work ahead of me...