16-50 vs 16-80 vs 16-105
I explain my problem. I have a 16-105. I´m happy with it exept when taking group shoots, people on the corners get their faces distord and streched. The A77 Auto distortion fix improves centers but makes the corners even worst.
I am searching fo a lens that dosen´t do this, or at least not as much
I think you're going to find that all the zooms are going to squish circles (a person's face is more or less a circle) in the corners.
See if Fisheye Hemi does any good with your existing distorted people shots. There's a free trial, and I've had some decent success using it with an 8mm.