I have created a layer mask in which I have erased a number
of pixels around the edges of a bitmap, creating a nice
textured,torn-paper look. I'd like to use the bitmap--a series of
three gradient colors--in several different opacity levels without
altering the gradient. Is there a way to do this, or will I lose
the information stored in the mask once I replace the bitmap (I had
to flatten it, of course)?