You scanned pictures or the film? If you scanned the film 200dpi is not enough by far. Even from picture you might need more informations (pixels) for good color corrections. or... Is your screen calibrated? (is black really black?) or... Do you let the scanner or scanner-application do any auto-corrections? If you have no professional scanner/scanner-application turn auto-corrections off. or... In PS: do the corrections for each channel (r,g,b) individually (Strg + L, then use the pull down)... or... try to correct the gradiation (strg + m) or...or...or... hope it helps a bit sascha