I'm using Photoshop Elements 15 on an iMac running macOS Sierra, Ver 10.12.2. I just merged two photos using Panorama, flattened the layers, and tried to use Filter -> Correct Camera Distortion. The Correct Camera Distortion box opens, but none of the tools work (Vertical, Horizontal, etc.). I have used the distortion tools successfully before on other Panorama merged photos and cannot figure out why they've stopped working for me. Any ideas on the cause will be appreciated.
Oops! Color me stupid! I did not notice the "Preview" box was not checked.