There are a lot of ways to change the corners of a photo in Photoshop. You can make them more rounded, or make them more squared off. But one way to really change the look of a photo is to use a curve tool. To use a curve tool, you first need to create a new layer on your canvas. Then, select the Curve tool from the Tools palette and click on the corner of the photo you want to change. The Curve tool will give you many options for how you want to change the corner of your photo. You can make it more rounded, square off, or even have some curves that go all around the image. If you want your corners to be really different looking, then you can also use an effect called Bevel. With Bevel, you can make your corners sharper or softer. But be careful not to overdo it – too much Bevel will make your corners look too sharp or too soft.