Originally posted by monochrome FWIW, I also have second-hand '50's and 60's lenses that work as they did when they were new. Same for second-hand cameras.
True. 99% of my Takumars (not the ones that were abused beyond repair) are SO GOOD mechanically that they're still focusing buttery smooth. And those are 50 year old lenses! But those were the days... Takumars were built with the tightest tolerances possible, with the very best materials, with the very best lubricants, by the very best personnel they could find, QC'd by the most strict inspectors. Otherwise I cannot think of a valid explanation proving why my Takumars do not have coating defects, oily blades, stuck diaphragms, tight or loose focusing, or even rattles. None of them! No, Takumars are truly gems.
This is in stark contrast with anything German and Russian I have ever used. There are only a few exceptions, but most of those lenses did not withstand the test of time. They ALL have issues. Finding a unabused Takumar with issues is rare, very rare!
I don't have that much faith in today's lenses because plastics and electronics do not age well. And there's no exception to the rule unless we're talking about the rare stuff like the 125mm f/2.5 Macro-Apo-Lanthar (which are very Takumar-like).