Lensfun
Library to correct optical lens defects and lens database
NOTE: We are moving this project to GitHub!
Digital photographs are not ideal. Of course, the better is your camera, the better the results will be, but in any case if you look carefully at shots taken even by the most expensive cameras equipped with the most expensive lenses you will see various artifacts. It is very hard to make ideal cameras, because there are a lot of factors that affect the final image quality, and at some point camera and lens designers have to trade one factor...