Quote Originally Posted by stradibarrius View Post
I was wondering if there is a result difference between a prime M/F and Autofocus from the same manufacture. Of course I am talking about equal quality, era, vintage etc. lenses.
I have never really thought about this until now.
Not looking to start a war just looking for opinions.
I assume you're talking about the effect of autofocus on image quality? That'd depend entirely on the user. Someone focusing manually is usually more careful about focusing precisely where he wants, while someone relying on autofocus may or may not hit it and may not notice until he gets the images back. Gross generalities, to be sure, but certainly true from my own experience.

If, on the other hand, you're talking about, say, the optical difference between the FD 85mm f/1.2L and the EF 85mm f/1.2L, there is no difference from what I've heard. But if you look at another pair like the FD 24mm f/1.4L and the EF 24mm f/1.4L, there may well have been optical improvements incorporated in the new lens.