Originally posted by fireforsave I was wondering if anyone has owned and compared these two normal 1.4 Vivitars. The 55mm has a 55mm filter thread and is only found in M42. The 50mm has a 49mm filter thread and is only found in Pentax K. I'm building a set of Vivitar lenses and need a ~50mm. The 55mm is a rumoured Tomioka design but researching that leaves a dead end. Overall I just want to know if there is a significant optical difference between the two. Thanks for any help!
I can't help, but that is an interesting question. It reminds me that I seem to find better build quality in m42 lenses made before the K-mount was invented. That doesn't mean that there aren't exceptions, and of course the K-mounts can equal or exceed particular m42 in image quality areas. In any case, I never hesitate to choose an m42 lens if it has a good reputation (or is cheap enough to try out without a review), and in fact most of my prime lenses are m42!
I hope you can find good guidance about the two lenses you're inquiring about!
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