[Gimp-user] Layer Masking

[Madeleine Fisher <animatrix1490 gmail com>]

Hello! I am an artist trying to create a certain effect that I can't seem to figure out on my own:
In a picture, I have areas in shadow and areas in light. I want the light parts to be the "real colors" (brown barrels, red apples, etc.), but in the shaded areas, I want it to be purple--perhaps a purple version of the "real" colors.

Any thoughts? (Especially ones that aren't too technical?)

Thanks in advance!