Here's some basic data. It may help.
Jupiter : http://www.baierfoto.de/russobj/objektive/jupiter.html
Industar : http://www.baierfoto.de/russobj/objektive/industar.html
I went through a number of lenses, a Jupiter 3, Industar 61N, Jupiter 8, Industar 22, and Industar 50 for use with a Canon RF and a Fed 4A. Minus the Jupiter 3, I still own these lenses. When I had the Jupiter 3, I was not particularly impressed with my copy (sharpness wise). Now that I have more experience with LTM cameras I wish I had it for retesting. The aluminum body Jupiter 8 is of fairly low quality (build wise), though it is definitely sharp enough for general use. It has no click-stops which is a real shame. I currently consider the Industar 50 the sharpest in this bunch, followed by the 61N, and then the Jupiter 8 and Industar 22. The two collapsible lenses, Industar 50 and 22 are made of steel and have the best body build IMO. Finding M39/LTM lenses with glass that is in pristine condition can take a bit of time and effort. But, they are out there. I ended up ordering three of these lenses through eBay sellers in the Ukraine.
Last edited by X. Phot.; 09-13-2011 at 02:33 PM. Click to view previous post history.