light leaks around seams, why and how to fix [SOLVED]
AbnerK
Posts: 718
Hi,
for a while now I've been getting light leaking between seams on G8.1 figures. I've ignored it and fixed it in photoshop but, today I decided to try to fix it in Daz so, I used content aware fill to remove any possible missing material at the edges of my maps, there was already a 16 pixel fill so there shouldn't have been any gaps anyway. Even after filling any gaps to the edge of the maps on both diffuse and SSS I've still got light leaks. How can I fix it. I'm using G8 maps with the g8 UV on 8.1.
light leak.jpg
400 x 600 - 150K
Post edited by AbnerK on
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I also had this happened recently on an 8.1 character if I had a rim-light. I couldn't find a way to fix it other than avoid the character having deep shadows and/or post-work. So I'm keeping my eye on this thread in case someone knows how to fix it or why it happens.
Oh, I'm glad I'm not in this boat on my own. Were you also using the G8 UV's?
Yeah, thanks photoshop for making this easier to fix. It is a bit time consuming though whichever method you use if you care about a proper repair.
It is not something I have observed, or I might just have overlooked it.
Can you give an example of what you are doing to get this problem.
Same. Not something I have ever noticed either
not really helping a fix though.
I've only been able to connect it to the HDRI providing rim light. As you can see in my example, rotating the HDRI gets rid of the seam. And then not using the HDRI entirely also provides no seam. The seam's color corresponds with the character's translucency. However, I don't know why sometimes some characters get it and sometimes they don't (as I use HDRI's as rim lights a lot). It just so happened that when I was working on a promo a few day ago using this scene, that I got said seam. (Click for a bigger image). BTW, this is using Genesis 8.1 UVs, so the seam corresponds where the "Head" and "Body" surfaces meet.
That is a tough one to reproduce and troubleshoot.
Although my guess is it is an Iray bug (feature?). And I would guess related to translucency.
I assume it comes when the HDRI main point of light is behind the character.
I tried to do some quick test, with G8.1F (Clara), rotating an HDRI with main point of light behind her in 20 degrees step, but no luck in reproducing it.
One could try placing a plane behind the character (out of view for the camera), and see if that can blocks the leaking.
Isnt this caused by displacement maps not 100% matching on seam.
That's what I thought at first, but taking the displacement off didn't fix it. Taking off the HDRI or adding a front light got rid of the seam.
I get the problem when I use a displacement map on a surface, say the torso. Even if the displacement map is strength 0. Remove the displacement, problem goes away. However I want a displacement.
Strangely if I get the system to render direct to file I get the problem but if I ask it to render to a new window I don't. Diferent render engines or versions?