"The Equalize command redistributes the brightness values of the pixels in an image so that they more evenly represent the entire range of brightness levels. When you apply this command, Photoshop finds the brightest and darkest values in the composite image and remaps them so that the brightest value represents white and the darkest value represents black. Photoshop then attempts to equalize the brightness--that is, to distribute the intermediate pixel values evenly throughout the grayscale."
Ben eigenlijk wel een beetje benieuwd naar het orgineel :)