Quote Originally Posted by rich815 View Post
When it comes to older and particularly "user" grade Rolleiflexes, the overall condition of the camera and the lenses have a FAR more impact on results than the comparison of the different types of lenses. Many of these older/user cameras have front standards a little out of whack, or backs that do not close as tightly as they should, or focusing screens that are not altogether flat or straight, etc. that can make one lens seem to perform better than another. I have a feeling a large majority of these "I had this one and that one and that one was better..." comparisons are more the individual cameras than the actual indication of which lens is better.
That is a valuable point that really deserves more emphasis. I mentioned earlier that I tested a lot of these lenses over the past year. That was largely to check focus (and camera function). In the process I got to see a lot of side by side comparisions at proper focus (and used up a fair bit of film). More than half of the Rolleis I checked needed at least slight adjustment (which was done).

I'd also add that nearly all of the old Tessars and Xenars I saw had at least slight haze on the surfaces in the air space between the first two elements (which I cleaned).

Because of all that (and more), casual observations about lens performance seem very unreliable to me.