Upload & Sell: Off
You are right at the very lower right corner of the picture, and that 35-70 looks excellent. Amazing zoom performance, especially at f/4. The crop is such a small portion of the photo, and the drop off is sudden enough for the 50, that I doubt his setup was off, though it would be interesting to know if each corner looked the same (ie. symmetrical corner softness.)
edit: reread the posts, and he says the 4 corners are the same. Very interesting. Wonder if this is typical of the lens. Seems hard to believe with a macro lens, where you'd expect a flat plane of focus, or flatter than normal. I have a hard time deriving equivent MTF's on those links as they never use the same f/stop at 50mm, which I'd think would be necessary in order to control the variables.