Quote Originally Posted by E. von Hoegh View Post
Edit - As for the Industars, the I-50 is an improved version of the I-22, both are f:3.5 Tessars. The I-61LD is an f:2.8 Tessar using a lanthanum glass element for better correction.
I am pretty sure there is more variation between one lens and another in the same serie than from an I-50 and an I-22... If you can't collapse the lens in your camera for whatever reason, I would choose the I-61 (whatever flavor) or even the dispartaged I-26. Too both I-61 and I-26 are easier to use with a filter (try to change the I-50 aperture with a filter in place... ).