I was trying to explain this to Urataros, but I so suck at teaching stuff and I thought actually trying to explain with images would be better. So! If any of you iconist out there have the same problem, I'm putting it up here for everyone to see \o/ Without further ado, I present you BLACK STAR'S BIG GUIDE ON HOW TO SHADE MANGA PANELS THAT ARE ALREADY SHADED AND GET RID OF THAT DAMN GREY.
So you find yourself wanting to color/icon that really cool panel. You think "man! It's already shaded, too, that's going to save me tons of work!". So you open photoshop (or whatever you use) and start coloring. You put your fancy layer in multiply, and color all the skin. There's only one problem. The awesome shading is grey and makes your character look like some kind of zombie. LIKE THIS.
So, what do you do? You make a new layer under the original one and put it on soft light! Then you start coloring just the grey areas, with the same color you used for the original skin layer. Because I'm a lazy ho, I actually just select all the grey areas with the poligonal lazo, then fill them with color using shift+f5-- but whatever works better for you.
This is what you'll get:
A lot better, huh? Still greyish, but decent. So, what do we do to make it better? Let's go the lazy way. Duplicate the layer you just did, put it above the original layer, and set it on multiply. Ta-daaan!
This is what you'll get:
COMPARE TO THE ZOMBIE ONE FROM BEFORE, A LOT BETTER, RIGHT!?
If you couldn't understand anything at all, blame it on... I don't know, anyone but me ok :(