Thanks guys, great informations
OT: Collapsible Industar 10 and 22 look quite similar. What is the main difference? (talking about the glass)
It seems to me that 10 is more coated than 22 (?)
I am eager to get LESS coated version - uncoated Ye-Old-School lens are special to me
The I-10, -22, and -50 collapsibles ALL look similar. However it's the I-10 which looks most different.
One, the I-10 appears to be shorter than the I-22 and I-50. And many I-10 are actually uncoated- those from before and immediately right after the war were uncoated. The coated ones look more purple, but not necessarily "more coated" than the I-22 or I-50.
There were a few I-22 which were uncoated, but these would be vdry uncommon because AR coatings became prevalent shortly after the I-22s were released. The presence of a red "
П" indicates
the lens is coated.
As mentioned previously, of all the collapsible Industars, only the I-10 had levers for setting the apretures. The I-22 and I-50 used rings. Some early I-22 may have also used levers.
As for quality, it's very hard to say what optical advantages the I-22 or I-50 had over the I-10. Literature would say that the I-50 came out as replacements for the I-22, and that both the I-22 and I-50 were in turn improvements over the I-10. However, FED seemed to think that the I-10 was good enough, and continued using it until they replaced it with the I-26 and later, the I-61.
Personally speaking, I don't see any differences either. However, I do see that these Industars can do better in many ways than the average same-looking Elmar.