Title says it all.
I am looking for a macro lens mainly for scanning my 6x7 negatives that matches the ridiculous resolution of the 5DSR. For now I am looking at the Canon 100mm 2.8 USM Macro (not L!) or the Sigma 70mm Art Macro, but any experience with other glass is highly appreciated!
Thanks fellow scanners!
Difficult question if we’re looking at lens test data. Most measurements don’t cover macro situations…
Measurements on dxomark.com show that the tested lenses with a macro designation look similar.
I use the lens you mention on both EOS 5D3 and M6 bodies. My usual ASA 400 645 negatives can be captured with good enough quality and stitching multiple shots only brings out the grain more clearly.
I got really really good results out of the sigma 70mm macro art! That thing has superb sharpness and can easily keep up with the 50MP of your 5DSR.
I’ve used the Canon 100mm macro and the Canon 100mm L macro and both render great results.
The lenses already suggested are all good lenses but none are optimised for the task you have in hand. In your shoes, I would spend that budget on a Canon bellows unit and a second hand macro bellows lens. The lens need not be from Canon as bellows lens adapters are freely available and not costly.
Bellows lenses are optimised for reproduction at 1:2 - 2:1, have an almost perfectly flat field (essential to get sharpness across the whole negative) and have minimal chromatic aberration. General purpose macro lenses simply cannot do this as well.
You could look at Leica Macro Elmar 100mm F4, Olympus 80mm F4 or 135mm F4, etc.
Top quality enlarger lenses also work well such as Schneider Componon-S 150mm f/5.6 Schneider Kreuznach Componon 150mm f/5.6. Bellows needed and adapters are easy to find.
Best of all are line scan lenses if you can cannibalise from a broken scanner on ebay - Nikkor ED 100mm Scanner Lens from the Coolscan ED 8000/9000 or the lens from the Minolta Dimage 5400 (best of all). Again, a bellows and adapters will be needed but the results are spectacularly better than any other lens.
That said, the Sigma Art and the Sigma 70mm F2.8 DG are very good and outperform the Canon 100mm F2.8 which is disappointing by comparison.
Adaptable (high quality and price) gear with bellows and lenses: Extension Bellows
Getting a bellows solution has one major advantage: The bellows is attached to the copy stand and you can change camera and lenses without touching the setup. This helps if you can’t dedicate a camera and lens to just scan negatives…
As for “good” or “better” lenses, I don’t really care that much, and so far, I’ve not been able to pin any bad shots to bad equipment. Usually, it’s sloppy technique.
You are right about a bellows set up…and using a bellows with a slide copy attachment (mostly for 35mm) has the added advantage of eliminating all problems of stray light getting into the system.
You are also right when you say most sub-optimally sharp images are usually more down to technique than equipment but things get more serious with reproduction at 1:1. Most lenses perform worse at the edges of the frame and that has to be accepted. If that film frame with poorer edge quality is then photographed with another lens that also has quality fall off at the edges, then the unsharpness is compounded. When you add field curvature and chromatic aberration to that, you have real problems. That’s why using a lens which is optimised for 1:1, is critically sharp edge to edge, has a perfectly flat field and minimal chromatic aberration, is so important in achieving a great scan. And that’s why I use a bellows reproduction unit and an apochromatic line scan lens.
By the way, the old Canon MP-35 bellows lens would be a great choice. It still knocks spots of all other Canon macro lenses - but of course it will only work at macro magnifications.
