USE: GOOD FOR CORRECTING WONKY HORIZONS
Unless you use a tripod with a spirit level, when you open a landscape image in photoshop, you may find that it needs via the image >Image Rotation menu, but you can also it manually using the crop tool. Once you have selected the entire image with the crop tool, if you hover your cursor over the corner widgets and rotate the image until the subject looks straight and commit to crop. As the image now will be titled, you will find that canvas is showing. You will need to crop this canvas out. Alternatively, if they extra canvas space works for image, select the Clone Stamp Tool and fill in the blank canvas by making a selection from the edges of the image.