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Anthony_4033
4-Mar-2004, 22:03
I've done a lot of reading on this site, and I'm really glad that all of you are out there. I have a couple questions.

I'm doing a macro project that's going to be exclusively 4:1. I'm looking for sharp. (I'm used to hasselblad's and panavision).

After reading Q.-Tuan Luong's f-stop article, and Ernest Purdum's Macro lens article, I find the big question I have is, am I better off trying to find a really good enlarger lens and reversing it, or should I go for a really good macro lens? I have a hard time believing that an enlarger lens is going to be sharp enough.

I'm renting lenses, so cost isn't really the issue; sharpness is the only thing that matters. I'm running a sharpness test this weekend. my choices so far are a 120mm f5.6 Macro Symmar, Nikkor 120mm macro, and a caltar/schieder 120mm 5.6 super angulon(not a macro). I'm looking for others, but they are hard to find.

Now here's the hard question for you guys. Am I in the wrong world of cameras? Should I just go back to the hasselbald and a bellows, and bite the bullet in grain when I blow these things up?

Thanks for any help. I'm going to go and read on. Thanks for building a great site.

Anthony

Michael S. Briggs
4-Mar-2004, 23:53
The two macro lenses that you mention, the 120 mm Macro-Symmar and the 120 mm AM-ED Nikkor, are symmetrical lenses which are thus optimized for 1:1. For a reproduction ratio of 4:1, I suspect that you will do better with a reversed enlarging lens. The difference might be small since 4:1 is not drastically different from 1:1, and the difference will also depend on the taking aperture. If you pick an enlarging lens that is excellent for 4X enlargements to a print, then reversed, it should be excellent for 4X enlargements to film. Coverage shouldn't be a problem since your subject is approx. the size of a 35 mm film. Even so, I would pick something like a 63 to 105 mm enlarging lens.

I don't know why you think it is hard to believe that an enlarging lens will be sharp. They are designed to image a flat film to a flat paper. If the lens is good enough for your prints, why isn't it good enough (at the same reproduction ratios) for your film? Even looking at the projected image with a high power grain magnifier, the image quality is excellent. The complexity of the optical designs is similar to the macro lenses you mention, typically 6 elements in 4 groups. If you want the best, consider the Rodenstock Apo-Rodagon-N or the Schneider Apo-Componon-HM.

I don't know of any true macro (meaning magnifications significantly more than 1) lenses for LF that are made today. The better recent lenses are hard to find and expensive.

The difficulty of doing 4:1 with a LF camera depends on your setup. For example, with a field camera, you might have difficulty getting the standards sufficiently parallel to each other and to the subject, and you might have problems with vibration.

Armin Seeholzer
5-Mar-2004, 01:32
Hi Anthony

If you only want the best for it then take the M-Componon from Schneider they are especially for enlargments of jewelry from 2:1 up to 12:1. But the second best would be a Macro like the Schneider, Rodenstock or Nikon! I'm very happy with my Rodenstock macro 120mm but used it only up to 2:1 till now! Good luck!

Dan Fromm
5-Mar-2004, 05:07
Get a 40/4.5 Luminar and don't look back.

If you can't find one, front mount a reversed 55/2.8 AIS MicroNikkor. They're inexpensive enough that you can just buy a used one. Front mounting will require an adapter; try SKGrimes, who made one -- male 52x0.75-to-male 40x0.75 -- that holds the lens in front of a #1 for me a while ago. At 4:1 vignetting by the shutter shouldn't be a problem on 4x5, but at lower magnifications it will be. I'm not particularly kidding about the MicroNikkor.

But the best thing you can do is take all of the well-meant advice you get here with many grains of salt and be more forthcoming about your project. In particular, what final print size are you aiming for? How are planning to illuminate your subjects? How deep are your subjects? Which emulsion do you have in mind to use? Do you live under a bridge and subsist on goat?

Cheers,

Dan

Anthony_4033
5-Mar-2004, 08:58
Thanks for all the help. I'll chack again later for more, and I'll write back when I finish the tests. This page was a wealth of help.

Anthony

Ted Harris
5-Mar-2004, 11:41
Dan just scratched the surface when he asked "In particular, what final print size are you aiming for? How are planning to illuminate your subjects? How deep are your subjects? Which emulsion do you have in mind to use?"



Choosing the best lens for the job is important but there are many other important factors. First when you use the term 'sharp' you are really talking about several diffferent but related factors such as reolution and accutance. The lens, the fim and your final reporduction choices all contribute. BTW, if you have done lots of macro work then you probably already know all this and I apologize. If nothing else I strongly suggest you read at least one book, "Image Clarity:High-Resolution Photography" by John B. Williams that pulls all this together.



Next, staging and lighting can be critically important, especially when photographing small objects. I could go on for many paragraphs on these aspects but you will get much more from the book. Having said all that, large format the right choice? Maybe. A field camera is unlikely to do the job. A monorail will give you more flexability than most of the MF solutions, even with bellows but there are some specialized solutions that you may want to consider. I have done a lot of macro work at 4:1 and larger for years using LF and prefer both the way it allows me to work and the size of the negatie or transparancy.



My main point which I don;t want to lose sight of is that the lens you choose will be irevelent if you don't properly control many other factors.

Dan Fromm
5-Mar-2004, 11:57
Anthony, Ted made some good points. He also made me wonder whether you've done your homework. Apologies for the implied insult. Too many people post the wrong questions on bulletin boards and get answers that don't really help them.

If you haven't read them yet, you'd do well to get and study Lester Lefkowitz' book The Manual of Close-Up Photography and Kodak's publication N-12B "Photomacrography." They'll give a good sense of what's important and of limits. Both are out-of-print, can be found quickly through Amazon and other on-line sources of used books or slowly and, usually, at a lower price, on eBay.

Cheers,

Dan

Dave Schneider
5-Mar-2004, 12:38
A 40 or 55mm lens? Wouldn't that leave you with about 10 mm from the center point of the lens to the subject? How would you light something in that situation? I have used a 150mm lens for 1:1 and find the lens to subject distance too close for comfort.

Dan Fromm
5-Mar-2004, 13:36
Dave, Anthony wants 4:1.

If I've done the arithmetic right, at 4:1 the front node to subject distance is 1.25 focal lengths. Rear node to film distance is 5.00 focal lengths. Doing that with a 150 requires a fairly long camera.

The minimum front node to subject distance, reached at infinite magnification, is the lens' focal length. A 40 or 55 mm lens' focal length isn't 10 mm.

About lighting. If Anthony's shooting 4x5, at 4:1 his subject will be fairly small, no more than 1" x 1.25". A 40/4.5 Luminar, if that's what he uses, is pretty skinny and long. There's lots of room for slightly oblique lighting, especially if he puts the lens on an extension tube or uses something like Linhof's macro tube. There's no reason why the camera's front standard has to be right up against the subject.. Axial illumination is another problem, but there's room for a beam-splitter between lens and subject.

Cheers,

Dan

Ernest Purdum
6-Mar-2004, 11:47
I'll watch for the results of your tests with interest. To go out on a limb, and predict, I think you will find the results for the first two lenses you mention satisfactory, and those for the Super Angulon very much less so, particularly if your lighting illuminates much more than your subject.



Testing can be quite difficult. It's hard to keep other factors from affecting the results. Particularly in macro work, vibration can make the very best lens look like trash. At only 4:1, you probably won't see any indication of a problem when composing and focusing, but it can be there, nevertheless. I suggest using an air release rather than a cable release. Stand still briefly before making the exposure. Listen for noise that suggests a vibration source, like a truck going by, and wait until it is gone. I hope that your camera and your subject are supported together. I once used a camera on a tripod, and the subject on a tall light table. If I wasn't particularly careful, the two separately supported units were certain to move individually.



Do you know about "aerial image focusing". It's a technique frequently used in photographing through a microscope. It isn't used as often at low magnifications, but if you are going to be doing very demanding work like testing, it could help. You cement a small piece of clear glass with a cross-hair reticle on it to the frosted surface of your groundglass. The reticle side should be in contact with the screen. With a high power loupe, and no image on the screen, you focus the loupe on the reticle. Now, you focus the subject normally, then look at the image at the clear glass while moving your head slightly. Only if the image stays stationary in relation to the reticle is your focus right on.



Since you intend to rent, your choice of lens may be somewhat restricted. I would be surprised to find some of the good prospects available as rental lenses. The M-Componon, for example, would be an excellent choice, perhaps the best, but availability could rule it out.

My very best wishes,