Sharpen the Image Sharpen the Image What is this? When do I do this? Most image sharpening software tools work by applying something called an “unsharp mark”, which despite its name, actually sharpen an image. Illustrate in GIMP Whenever you want to emphasize texture or draw the viewers focus. How do I use this? It makes the image look crisper and the edges in the image more distinct. http://youtu.be/JQUDCX8N_rg What do all of the options do? You can sharpen the whole image or certain sections of the image. When do you sharpen an image?