i'm wondering if i really should keep my sigma 12-24 now that i have a full-frame sensor. 12mm is really ridiculous on full frame. perspective distortion and a half! plus 24mm effective via full frame + 24-105/4L IS is pretty dang close to the effective 20mm i had with the 20D + 12-24 while being much more useful due to the constant aperture, sharpness near(er) to wide open, and, most importantly, IS.
thoughts?
thoughts?