[QUOTE]\nOK, let me elaborate: Levels has only three *INPUT* sliders at fixed\npositions, where curves has as many as you want at any position you\nwant.\n\nBTW, that applies to Photoshop only, of course. For example Apple\nAperture has levels with five input sliders, and three of them can be\npositioned anywhere you want.[/QUOTE]\n\nWith Curve you can make as many marks as you wish, but it won't be easy to\ncontrol all the marks at once.\n\nLevel has more than 3 sliders (somewhere around 12-14 sliders). No, you\ncan't move up and down like Curve but you can slide Left/Right anywhere you\nwish.\n\nI don't know anything about Apple but I don't think it's much or any\ndifferent than Windows, and if Windows has more than 5 (12-14) then I bet\nApple should be close to equal. But I am not MAC user so I may be wrong.