What IS Sharpening & Why Do it?
"It’s really quite astounding the degree to which sharpening can affect the outcome of a photograph. It can render a photo useless as quickly as it can improve it. Used selectively, it can lead attention to the points of focus in an image, save portions, enhance others, and if it’s in a cavalier , can amplify a mistake and attract the wrong sort of attention. Along with saturation, it is the most commonly post process I come across. There’s this idea among many, especially beginners, that a sharp picture is a good picture, but truly the definition of both of those terms, ‘sharp’ and ‘good,’ are sort of nebulous.