I have a monochrome image, and would like to replace the colour with a gradient.
I assume the best way to do this would be to create a background layer with the gradient, and then apply the monochrome image as a mask. However, I can't for the life of me get this to work. If I copy the image, and then try to paste it into a mask layer, it just creates a new normal layer and pastes it there.
How to accomplish this?