sapiboonggames wrote:The direction of light I pick is right in front of him.
That's very unusual... what is the light source? Is there a story reason for it? What height is the source at? (eye level? stomach level?) How close is the light source? (With something like the sun it isn't going to matter, but if it's a spotlight, flashlight, camera flash, etc it could. If it's close enough, the parts of his body beneath the source would have light coming from "above" and the parts above would have light coming from "below.") If there's not a story reason for it, I'd say have light come from above because it'll be way easier to find references for.
In that pic, the light is coming from directly above... well, above-left; I'm not sure it's 100% consistent.
sapiboonggames wrote:The problem with photo reference is, I can't really see the difference between shadow and base color and highlight... Sorry for being so dumb...
You're not dumb; it
is hard to "translate" a photograph into cell shading. Photos are way more complicated. (I am definitely not practiced enough to do it without the additional help of anime/manga references.) It also may have to do with the lighting, because in some photographs there is a lot of it (bright light, multiple light sources), and little contrast with the shadow.
For example, this one would not make a good reference (shadow? what shadow??):
http://upload.wikimedia.org/wikipedia/c ... ouched.jpg
As opposed to this one, with some actual contrast (the light is coming from the right):
http://st.depositphotos.com/1371851/189 ... rtless.jpg
There's often some good contrast in the sun:
http://incommunseries.com/wp-content/up ... ackman.jpg
An anime example from Free! (sun from upper right):
http://1.bp.blogspot.com/-g4lcQ5qlMPk/U ... 24x576.jpg
An indoor example from Hakuouki (light from upper right):
http://bananamuffinblog.files.wordpress ... ot-141.jpg
Hope this helps!