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John Layton
6-Nov-2017, 09:17
Am just wondering if I can (or should) reverse my 180mm Companon-S enlarging lens for working in the ranges of appx. 1/4 to 4/1 for the 5x7 format? Anybody try this? Results? Thanks!

Jimi
16-Nov-2017, 03:38
Perhaps it doesn't exactly answer your question - but somewhat related information that might be of interest to you (post number 11 in this thread):
http://www.largeformatphotography.info/forum/showthread.php?141360-Small-but-powerful-micro-LF-lenses&p=1407024&viewfull=1#post1407024

Dan Fromm
16-Nov-2017, 06:05
John, y'r lens is optimized for enlarging. Small negative behind the lens, large print in front of it. This is the same as optimization for taking at magnifications below 1:1. Small negative behind the lens, large subject in front of it.

If you want to use it above 1:1 (small subject in front of the lens, large -- relatively -- negative behind) then you'll have to reverse it to get the most from its optimizations.

Advice to reverse the lens when working "closeup" is usually misguided and wrong.

John Layton
16-Nov-2017, 06:15
Of course! (doh...head slap!) - just thinking backwards...thanks for setting me right!

mdarnton
16-Nov-2017, 07:09
The other issue is what is degraded when using the lens "wrong". I assume you aren't copying flat objects, which the lens is designed specifically to do, in which case the direction the lens faces may or may not matter, depending on your subject matter. Theory is one thing; real life is another:Test.

ic-racer
16-Nov-2017, 07:30
I presume you are copying flat objects. In which case the rear of the lens would face the closer object, be it film or subject. If you have a laser alignment gauge for your enlarger, that can be used to line up the subject and film.

Pere Casals
16-Nov-2017, 08:07
Am just wondering if I can (or should) reverse my 180mm Companon-S enlarging lens for working in the ranges of appx. 1/4 to 4/1 for the 5x7 format? Anybody try this? Results? Thanks!

PD: El Nikkor 50mm, with 46 coverage, should cover 5x7 at gretater than 4:1 magnification.

PD: This wrong:

For 1:1 to 2:1 (onfilm_size : object_size) I would recommend Nikon EL 50mm 2.8 reversed, it is a 35mm enlarging lens but when reversed it works well for LF, as field and film planes are interchanged. For lower magnifications perhaps an EL 80mm would be the choice from 2:1 to 1:1. The 180mm can be suitable for 1:4, this is 1/4 of life size on film.

Think that with reversed lenses if you want a greater magnification you may want an smaller focal length.

Dan Fromm
16-Nov-2017, 08:51
Papi, at 1:1 a 50/2.8 El-Nikkor will cover a bit less than 90 mm. This isn't enough for 4x5.

Luis-F-S
16-Nov-2017, 10:15
John let us know what you end up doing and if you see any difference.

Pere Casals
16-Nov-2017, 11:21
Papi, at 1:1 a 50/2.8 El-Nikkor will cover a bit less than 90 mm. This isn't enough for 4x5.

Dan, you are right, magnification should be greater than 1:1 to cover even 45, it covers 46, so bellows extension determines coverage.

At 2:1 sure it covers 4x5 excedingly.

I'll make an exercise to calculate at what magnification it should cover 5x7...

Dan Fromm
16-Nov-2017, 11:36
Not at 1:1. Please respond to what I wrote --I did that -- not to what you want to believe.

Pere Casals
16-Nov-2017, 12:00
Not at 1:1. Please respond to what I wrote --I did that -- not to what you want to believe.

Dan, you are right, the 46 the EL 50mm does not cover 45 format at 1:1 it has to be a greater magnification...

I'll try to calculate at what magnification 50mm/46 cover 57 format...

John Layton
16-Nov-2017, 13:01
Am thinking more along the lines of 3D subjects in the range of 1/4 to 1/2 life-size, and for this I can mount the lens directly (without spacer) into the #1 Copal shutter which currently houses my 210 Sironar-N (verified this by comparing front to rear lens spacing with calipers).

As for 50(ish) lenses for L.F. macro work - here is a much larger than life-size image I made many years ago (watch movement floating on aluminum powder sprinkled on water in paper cup)...taken with the still-amazing 55mm f/3.5 micro-nikkor - reversed via a filter ring glued to a square of masonite and mounted to my 4x5 Crown Graphic - side lit with desk lamp - "exposure by light switch" method: 172063

John Layton
16-Nov-2017, 13:02
....and many thanks for all the great replies! I will report back soon!

Pere Casals
16-Nov-2017, 13:23
Not at 1:1. Please respond to what I wrote --I did that -- not to what you want to believe.


After calculating it, if I made no mistake, reversed EL Nikkor 50mm should cover 5x7" film at 3.91 : 1 magnification. Of course you were right and I was wrong...


172064

Bernice Loui
16-Nov-2017, 13:56
Think making a 5x7 or much larger print from 35mm film, except reversed. "Coverage" is NOT an issue depends on magnification-reproduction ratio.


Bernice

Dan Fromm
16-Nov-2017, 19:22
Am thinking more along the lines of 3D subjects in the range of 1/4 to 1/2 life-size, and for this I can mount the lens directly (without spacer) into the #1 Copal shutter which currently houses my 210 Sironar-N (verified this by comparing front to rear lens spacing with calipers).

John, before we all go farther into fantasyland, take a look at y'r Copal #1. I think you'll find that the front tube is threaded internally M40x0.75 and that the rear tube is threaded internally M36x0.75. You can certainly attach the shutter to the lens board of your choice, it has mounting threads for the purpose. Even better, according to Schneider, y'r 180/5.6 Componon-S cells are direct fits in a #1.

Fine, wonderful. Now tell us how you're going to swap the cells front to back or mount the shutter with lens backwards on a board. No need to tell me that I'm not a nice person, we already know that.

John Layton
17-Nov-2017, 05:01
.....just like I did back in the day with the Micro-Nikkor (see above) - by gluing a filter ring into a masonite lens board and the lens/shutter hangs backwards off of this. And hey...you can't fool us...we know that you're nice!

Dan Fromm
17-Nov-2017, 06:25
Thanks, John. Crude, but it works. FWIW, I've done worse.

Luis-F-S
17-Nov-2017, 07:38
John, I've got a 240 Componon-S that came factory mounted in a Compur 3 shutter. I bought it for 8x10, but I've yet to used it. Schneider did supply shutter mounted Componon-S lenses, so I can believe that the 180 may be a direct fit into a No. 1 shutter. The brochure I have from the 1980's says that "shutter mounted, Componon-S make great close-up lenses because of the flatness of field."

Luis-F-S
18-Nov-2017, 12:54
Here are a couple of shots of a factory shutter mounted 240 Componon-S. Note the secondary accessory threads on the rear cell group to mount to an enlarger lens board. The second shot shows a Durst Lapla mounted on these threads to be used in mounting in a Durst enlarger. I would suspect the 180 may be similar. L

172124172125

quine
11-Jan-2018, 20:20
Correct -- I have the 180mm Componon S in shutter. The end of the rear element also screws into a Durst LAPLA.