I made this model for a client who wants to print in full color sandstone. I uploaded to my own account to test it before sending it tool him but the color in the preview is wrong, it's way too light. What looks grey in the preview should be almost black. I uploaded a WRL model with a PNG image. I also tried JPG with the same result. Should I be concerned that it won't print right?
See if you have both the texture and a solid material color defined - WRL allows both to coexist and add up. (Solid grey would not be that unusual for a default color in a modeling software)
Defined in the software you mean? I've never heard of "solid material" color. However I have two other full color Models on Shapeways and the preview looks fine for both of them.
Yep. No idea what software you are using, but WRL allows both color per vertex (or even per primitive if you use the predefined sphere, cylinder, etc) and color by external texture file. As WRL is a text file format, you can look for Color nodes ("diffuseColor" etc with RGB triplets).
Oh vertex color. That I can do I don't think that's the case though since my other models look fine and didn't use that. I'm using LightWave 3D.