This is my fix for the Industar-69 28mm 1:2.8 pancake lens famous infinity focus problem. I read several tutorials and pieced them together and came up with this non-destructive hack that still allows an infinity stop and close focus stop with only one minor setback of the aperture scale mark.
I used a digital camera for this fix which I suppose 90% of the uses for this lens is but, if you have an old 35mm film camera with the M39, Leica screw mount (with a hinged or removable back plate) you can use this lens too, just use a frosted glass plate of some kind, a removable SLR focus screen works good, or I’ve even used scotch tape pulled tight over the film guides to focus test lenses.
Giving my 1937 Zeiss Ikon Contax II as best of a CLA (clean, lube, adjust) as I could without dismantling the mechanism itself, I doused with lighter fluid twice, avoiding the shutter slats, tapes and glue, which is fairly easy as, everything is on one side. then I oiled a few choice spots, avoiding escapements.
With the help from forum friends, I fixed a problem with the Infinity on the RF, the previous hacker put the longer screws on the RF side of the front plate and they were preventing the plano-convex lens from traveling all the way to the side. Continue reading 1937 Zeiss Ikon ~ Contax II CLA→