It's actually the normal that's making the fingernails blurry unfortunately :/ And I know nobody here would use parts of it but I've used the same image on other sites where I don't really trust everybody Actually, here's the diffuse full-size without any watermarks:
so you didn't do the normal map either, just the diffuse and specular.... or was this all photoshop, no highpoly geometry? the wrinkles on top of the fingers look very "hand painted" to me, they're a little too regular, thick and dark - it might also look a bit more realistic if you put a bit more red saturation into the…