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!
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!
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.in...=1#post1407024
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.
Of course! (doh...head slap!) - just thinking backwards...thanks for setting me right!
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.
Thanks, but I'd rather just watch:
Large format: http://flickr.com/michaeldarnton
Mostly 35mm: http://flickr.com/mdarnton
You want digital, color, etc?: http://www.flickr.com/photos/stradofear
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.
PD: El Nikkor 50mm, with 46º coverage, should cover 5x7 at gretater than 4:1 magnification.Originally Posted by John Layton
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.
Last edited by Pere Casals; 16-Nov-2017 at 13:20.
Papi, at 1:1 a 50/2.8 El-Nikkor will cover a bit less than 90 mm. This isn't enough for 4x5.
John let us know what you end up doing and if you see any difference.
Dan, you are right, magnification should be greater than 1:1 to cover even 45, it covers 46º, 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...
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