One of the nicest things for stitching is a shifting lens, which can make a very rectilinear wide angle view. Here's one done with the 85/2.8 tilt shift lens, on a DX format. Unlike the old shifting lenses this one goes to both sides without flipping over, so it's easy to keep straight on a tripod. With three shots including one in the middle, you get a nice double width. Except for the little glitch on the top edge, the uncropped result is nearly rectangular. My old 35/2.8 makes a nice stitch with equivalent width of about 16 mm. from shifting alone, but requires that the lens be rotated, which can jiggle the tripod.
I'm tempted to get the newer 24 mm shifting lens, but something about the price gives me pause.
