When using uberSurface skin, Why Veins pop out more in some Character textures?

nokoteb99

I use Vascularity product.
at http://www.renderosity.com/mod/bcs/vascularity-for-daz/96152/

i want defined veins. set the displacement high. And in the characters thta i did so far(which were mostly V4 textures and I had done females so far) even the black skin characters had defined veins.. But then i am now using vascularity on black skin males,
and i cant for the life of me get strong defined veins even though i'm using the same settings.

i've done couple of black males and couple of lighter skin males.
both the lighter skin texture character and the black texture character are using Ubersurface with Subsurface scatter ON. The lighter skin texture guy and the black both have displacement at 400% . The lighter skin guy has hard strong veins, the black one doesn't. He does, but they don't look as defined.

Why? Does it have to do with the texture ?
because when i did it with females with black skin texture, the veins did popout..so why not for the black skin male?

nokoteb99

PS The pictures above. The first one is the nonblack male, the second one is the black male. Both have the same Subsurface Scatter settings with Ubersurface.
And there is no light in the scene in neither of them.

nokoteb99

Well i don't know who saw my post but i have to say i fixed it.

The solution was the Specularity.
Yup, in the character where the veins were defined, the specularity was 12.3%

In the one where veins are not very defined. i had specular 0% , once i fixed that AND also the specular color up to 128 128 128,, then the veins came.
INteresting.