I was testing the new Reality with some characters from Fabiana, love her work, and I noticed something peculiar happening:
I stopped the render after just a few samples. There’s a nasty “crack” in the nose/eyes area. It’s likely that there’s also a crack in the forehead area but that is covered by the hair. Fabiana is one of the few content creators using the eyebrow component of V4. That is actually a great feature, I wish more people were using it. The eyebrow in V4 is usually hidden and the eyebrows are painted on the main face texture of Victoria. That presents a challenge when using SSS because we need to mask the eyebrows from being affected by SSS or they will look reddish in color. Using the eyebrow component of V4 solves that issue and it also adds the ability to deform it, providing a more realistic result. Thank you Fabiana for going the extra mile with your characters.
But, when rendering with LuxRender we see those nasty cracks. Those are caused by the intersection of geometry between the eyebrow component and V4’s forehead. Even though the eyebrow’s geometry is set to be transparent, the intersection makes it visible and that is not good. The solution is very simple.
- First we need to select the eyebrow in the V4’s hierarchy
- Second we need to make the hidden parameters visible. In Studio this is done by clicking on the pane’s menu and selecting Show Hidden Properties. In Poser we need to click on the pane’s menu button and select Show hidden parameters.
- Our goal is to move the eyebrow component away from the forehead of V4 and that is a translation along the Z axis
- Find the zTranslate parameter and enter the value 0.08
That’s all there is to do. A tiny, barely visible movement away from the surface is all that LuxRender needs to render the image as expected:
The same issue can happen, some times, with hair props. In that case it’s the skullcap that is interfering with the forehead. The character, in case you were wondering, is Jannika and it’s available at Renderosity.
I hope this quick tips was helpful, see you next week.