Whether it is photo retouching or simply a tone calibration of the image, this operation is fundamental to the printing processes.

Very often, on the web as in print, we are faced with images that do not shine for their brightness, for the dazzling colors, or for an appropriate balance of chiaroscuro.

A balancing process can make a difference and give the image a tone of greater authenticity or mysticism that would otherwise be foreign to it.

Sometimes, however, a photo editing process is essential to remove unwanted details from the image itself, or, for example, to erase the signs of aging on an old photograph, if not to restore luster to photos that an old technology does not gave the right prominence.

This and more is the manipulation of the image on the computer, sometimes too abused, sometimes necessary to make a photograph attractive and effective.