[WizenedEE]

From my experience, a binary image is stored as a grayscale image with values of 0 and 1. Since grayscale is usually 0 to 255, it's impossible to see what is 0 and what is 1. So I usually put it into mspaint and then use the color fill to get it. Of course, that's harder to do if you have lots of small particles and such.