The original scan of this picture of Joy's had an all-over magenta cast, as many of my old print scans had. I opened Joy's file in Adobe Camera Raw 4.1 and used the Recovery slider to tone down the bright areas and then moved the tint slider towards the green side to counteract the magenta. Really was an easy fix. Without camera raw the same adjustment of the magenta cast can be made with Color Balance. I still see a bit of a cast in the "fur" of the hood. Certain areas can be selected an colors adjusted there. If you go into hue and saturation and play with the sliders watching the areas with suspected casts, it's not hard to tell what needs adjustment.