Process notes for tinting the grey parts of the photomask. I took advantage of the fact that you can't color the solid black parts of a black mask because in Photoshop black is just the absence of color. (You can clip a solid color or use a color overlay effect on a black mask, but that doesn't give the black to blue effect I wanted). A Hue/Sat layer tints the paper underneath the grey parts of the photomask, making it look like the mask is tinted. You can control how much of the mask appears tinted by adding a layer mask to your hue/saturation layer and performing a levels adjustment on that layer mass. I had an additional problem in that I'd clipped my cat to the photomask and needed to prevent the cat from being tinted blue.

Final LO: https://ozone.oscraps.com/gallery/showphoto.php?photo=404271