I recently acquired this lens (Japanese MM T* variant) and have been using it on my 5D, mainly on test shots right now. I really like the look and feel of the lens, as well as how incredibly sharp it is in the center. However, I'm a bit concerned about the corners and edges...it appears 'soft' (even when stopped down to f/8 or f/11) and this has been holding me back from using it on photo trips for more 'serious' images. Is this performance typical for this lens, or is this something that can be corrected by servicing? Thanks for any help or suggestions.

I have not used the Contax 35/2.8, so I can't say what's normal or not. The Canon 35L's corners aren't that great at F8 or F11 either, so don't go there looking for a solution. Surprisingly, one of Canon's best 35mm is the 24-105L IS. I used it on the 1Ds2 and now the 1Ds3 and for landscape work, it does very well.

Judging by the Contax 35/2.8 MTF chart, it doesn't look like a strong corner performer (the PDF is available by clicking the link in the data table - PebblePlace Contax DB). The new Zeiss 35mm F2 Distagon gets excellent reviews, but some people have complained about purple CA.

BTW - don't bother with the Leica 35mm Summicrons if you're after sharp corners; they are only so-so too.