Well, in the image I am currently using, I have a size 75 px brush. I tried using Quick Mask in another inamge also, using only a 35 px hard brush, but with the same result. For some reason, I can't see the mask!
I also tried just using the mask anyway, to see if it was just a problem with the colour, but it didn't work. I masked an area, then exited quick mask, and there were no marching ants and duplicating the image only reproduced the entire image, not just the section I had supposedly masked. So it seems as though Quick Mask isn't working at all...
Thanks for trying to help!
GoddessEternal