Anybody used yamasaki lenses? I have the opportunity to buy a wideangle lens (90/6.3 MC) at what seems to be a good price. It's quite modern, at most 10 years old or so, so I guess it should be compared to lenses of the same vintage, but any opinions at all are most welcome. Even if you haven't tried one but want to say something anyway, that's okay too.

What I've found so far is that the lens is a 4 lens tessar construction, and that yamasaki optical have been producing large format photo optics since 1924, so they would probably have some routine, right?

If anybody has some spare time they could also enlighten me in how lenses can affect contrast.