I've got a photo of 2 walls of an ancient building. The walls are very tall and are perspectively challenged. I managed to get them vertical on the sides, but now the back wall appears to be leaning away from the viewer. Any ideas on how to get that wall to stand erect?
In Expert Mode, using the perspective crop tool, select your entire image. An alignment grid appears over the image - if an alignment grid doesn't appear then maybe the right tool isn't selected. You should be able to drag left and right (bottom) corner handles toward the center of your image to align the vertical grid lines with the sides of the building. When you're finished click the check mark to accept.