Yashikor or Yashinon. Which is sharper below f5.6 ?

I'm looking to upgrade from my Yashica 635,which has the 80 mm Yashikor lens, to anyone of the following which have the Yashinon lens: Yashica 12, Yashica 124, EM or LM. The Yashikor does what I need it for but I've been reading a number of opinions and recommendations about those cameras listed that have the Yashinon lens and I'm looking for feedback from those who have used the Yashica 12, 124, Yashicamat EM and LM as to the sharpness and image quality when the camera is hand held. I shoot mostly stationary subjects and I'm just curious as to whether it would be worth it to upgrade from what I already have?.

Thanks,

Doug

I had an EM with the Yashinon in clean condition and a D with the Yashikor. The Yashinon was better on the corners/edges but the Yashikor had better character to my eye. Maybe a bit less contrast at full open aperture but not enough for me to care with how easily that is adjusted in the darkroom/film development.

If your camera is a known quantity/recently serviced, I would make sure I had the best hood available, and maybe flocked the film chamber to reduce reflections, and then spend the money on more film and forget about the Yashinons.

no detectable difference cept to your wallet

I have owned a Yashica D with Yashikor and a 124G with the Yashinon. Both were decent, but I would say the 4-element Yashinon is better in terms of sharpness, particularly below about F8 or so. Both do have some edge softness below F8 or so.

I had a few yashicamat´s always found them well build and reliable, but the lenses are highly flare prone... i even had the trouble to coat the film chamber with telescope black material and build a light baffle in a 124... not worth the trouble...

autocords are better

rolleis are even better

I had a later Yashica D with the Yashinon, and a earlier Yashica D with the Yashikor. The only difference I noticed was that the Yashikor seemed much more prone to flare, I don't recall ever having trouble with the Yashinon but that Yashikor seemed to flare unless the sun was directly behind me. Maybe it was just me or maybe it was just my example.