I can show examples if need be, but this is just an abstract question for now.
When I try match photo I very carefully line up a couple of red lines, and a couple of green lines, and you would think the blue lines would be vertical. They often are not, and you have to put the red and green lines into the wrong place to force blue to be correct, or live with the not vertical blue lines.
My guess is that fish eye effects are at play. Does that make sense? Are there ways to correct a photo before the match photo stage?
I think I’ll ask in the Photoshop forums too, it could be a common problem without even considering the SketchUp use for photos.