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Pics2
6-Apr-2013, 04:13
Hi,
I'm looking for decently priced lens for still life (not necessarily a macro lens). I found few Rodenstocks 105 and 135 for good price. Since I have no experience with LF yet (building up my first combo with Cambo SCX) I got confused with minimum focusing distances for these lenses (according to Rodenstock data) - 135 APO Sironar Digital - 3m or 10ft, and 105 is 1.8m or 6 ft. Since I work with smaller formats lenses, after comparing these numbers, I got to the conclusion that it is impossible to get close enough to make a picture of anything smaller than a medium sized postal box, for example. Am I reading the data wrong? Is a macro lens only solution for still life, even though I don't do extreme macro work? I wanted to avoid a macro lens in my beginners setup, since those are very expensive, and I wanted to purchase a digital lens since I work with Phase One digital back. What are your suggestions?
Thank you very much!

Dan Fromm
6-Apr-2013, 05:54
If you can provide the extension, every lens' minimum focusing distance (front node of lens to subject) is the lens' focal length. How well the lens will perform focused that close depends on the lens.

You misread or misunderstood Rodenstock's recommendations. They give lenses' minimum focusing distance on a shift or panoramic camera when Rodenstock's FocusMount is used. The SCX is not a shift or focus camera, doesn't need to have the lens mounted on a Rodenstock FocusMount, and will focus as close as the lens' focal length and the camera's bellows will allow.

Your mind has been warped by using lenses in focusing mounts. View cameras allow more flexibility.

If you can afford a digital back you can afford a macro lens.

Pics2
6-Apr-2013, 06:41
Thank you Dan for your reply! It's much clearer to me now.

Bob Salomon
6-Apr-2013, 07:09
The Sironar-N/Sironar-N MC/ Apo Sironar N are corrected for 1:20 with 1:10 being the minimum magnification for these lenses. The Apo Sironar-S is corrected for 1:10 with 1:5 being the minimum.
The Apo Macro Sironar lenses are corrected for 1:5 to 2:1.

That doesn't mean that you can't use the first lenses at 1:1 or the macros at infinity but their performance will be very comprimised compared to using the lens designed for the job.

Pics2
6-Apr-2013, 07:47
Thank you guys! The message is clear - I need to get a macro lens. So, I'll make another try to save some money, here is the question (or conclusion) - for the still life digital back job, it is better to get a no digital macro lens like Schneider 120mm Macro Symmar HM than a standard digital lens like Schneider 120mm APO Digitar? Would non digital macro lens still outperform standard digital lens at close distances?

Doremus Scudder
7-Apr-2013, 01:48
FWIW, I do a fair amount of tabletop work with a standard 135mm plasmat. I'm sure it is not at its best with repro ratios less than 1:10 (but likely not more than 1:5), however, for prints up to 11x14 from a 4x5 negative, the image degradation is negligible. 8x10s are way crisp (this is my normal print size for tabletop work anyway). Give your 135mm a try and see how you like it.

Best,

Doremus

Bob Salomon
7-Apr-2013, 03:20
Best perfomance will be with a dedicated digital macro lens like the Apo Macro Sironar Digital 120mm. A non digitel macro lens would be the next best. That digital macro would be superior on roll film as well as on digital.

Pics2
7-Apr-2013, 04:32
Thanks Doremus and Bob for the valuable info!

lenser
7-Apr-2013, 10:56
I can't give technical details about ratios and distances, but I did a bit of free lancing for a sporting goods company several years ago and one of my assignments was close ups of fish hooks. (Glamorous, I know!) Even on very small hooks, I used my SCX with a 210mm Caltar II. The subject did not fill the frame, but the results were surprisingly clear and quite sharp. I was once told that wide angle lenses gave superb results as near macro glass and my experience with a 90mm Caltar II has born that out.

Bob Salomon
7-Apr-2013, 11:07
I can't give technical details about ratios and distances, but I did a bit of free lancing for a sporting goods company several years ago and one of my assignments was close ups of fish hooks. (Glamorous, I know!) Even on very small hooks, I used my SCX with a 210mm Caltar II. The subject did not fill the frame, but the results were surprisingly clear and quite sharp. I was once told that wide angle lenses gave superb results as near macro glass and my experience with a 90mm Caltar II has born that out.

A macro lens will be good to the edges and corners as well as the center.
If the images were good enough for one catalog does not mean that they would be acceptable quality for other catalogs or uses.

If you take a LF wide angle far enough out of its optimization range color banding can occur while it will not occur with longer lenses at the same range. In addition, the shorter the focal length the greater the foreshortening. And this would reproduce the shape of the original incorrectly. So, unless the problems associated with a WA for macro is wanted intentionally the use of them for macro is not usually recommended.