Quote Originally Posted by holmburgers View Post
Take this with a grain of salt cause I'm going off purely anecdotal evidence, but how about a Schneider-Kreuznach 180mm Symmar convertible?

I've heard that this symmetrical and relatively simple design keeps a very flat field and I'm guessing(?) it might cover 8x10" at macro. It's suggested for 5x7" as a normal lens.
Not symmetrical, no simpler than any other 6/4 plasmat, and not particularly good close up.

The OP asked an unanswerable question and ran away. Unanswerable because without knowing the range of magnifications he wants to work at we can't know how much coverage is needed. He didn't even say why he wanted a 180.