How do you make the grey pixels in a scanned hand drawning more dark or more white? I a friend taught me the method once... but I forgot, I only remember that it involved something with the Channels (RGB, Red, Green, Blue) and you had to select them all and... I forget the next step, but remember that opened a window with a graphic of what I believed was a representation of how much of each shade of gray there was in the file/layer, you could tick with it a bit and make the shades of grey to become darker or lighter to get stronger/better lines to work with.
