When you’re adjusting the lens distortion for a wide-angle or fisheye lens in the Lens Correction filter in Photoshop (Filter>Lens Correction), the result can sometimes look stretched. If this is the case, go to Camera Raw (Filter>Camera Raw Filter), click on the Transform tool (Shift-T) at the top left (the one that looks like a perspective grid), and then use the Aspect slider to fix the stretching. You could also use the Lens Corrections panel in Camera Raw if you like.
This tip previously published in Colin Smith’s Photoshop Tips column, in the January, 2020 issue of Photoshop User magazine.