Glowing fingers with SSS

ttimm

Hi all, I've been enjoying making scenes in DAZ so far, but rendering is a completely different story. I played with iray soem, but it seems way to advanced for me, so I thought I'd see if I could figure out what I'm doing with 3Delight first. Even then, I am having issues, particulary with the glowing effect that comes with SSS.

My characters fingers light up in renders as though they glow. I have been through the surfaces pane on the hands and tried tweaking every setting I thought might help, to no avail. The best results so far are that I turn SSS off for the hands (they render in a soot-black hue, but hey, no glow!) or I turn the SSS strength down, which softens the glow, but eventually renders the hands black again the more I turn the strength down. Any other setting either exacerbates the glow, or makes no difference.

Please tell me there is a solution to this!

Richard Haseltine

How are you lighting the scene?

ttimm

I'm using the scene lights that came with the environment/architecture, and then attempting to do a three point rig set up based on what I read in the tutorial. The effect happens with or without the three-point set up. They are all defualt DAZ lights from what I can tell (I haven't purchased any light packs yet).

I'm really new to this and I trying to learn what I can, but ultimately I am reaching around in the dark. Here is a shot of what it looks like though

 

Richard Haseltine

it does look as if at least some of your lights aren't casting shadows - that with SSS tends to product undesirable results.

ttimm

Thanks, I checked that out. Unfortunately it didn't have any good effects. I had one light with a deep shadow set to it, the others had none. When I changed the others, everything rendered black, not solid, but an exteremely dark room with only silohuettes kind of visible. I switched them over to ray traced, same thing.

The materials I was using had the AoA subsurface shaders, and when I switched them to DAZ default, the glowing went away, but the skin got really light.

Anyhow, I thought I would at least report back and see if there might be anything else I might try. I appreciate the suggestion so far though :)

 

Thanks!

 

Richard Haseltine

Try selecting the room and turning Cast Shadows off. Or try replacing the lights, which I suspect are infinite lights and so shining from outside the room, with local lights (spots or point lights) inside the room.

mjc1016

Richard Haseltine said:

Try selecting the room and turning Cast Shadows off. Or try replacing the lights, which I suspect are infinite lights and so shining from outside the room, with local lights (spots or point lights) inside the room.That'

That's what it sounds like to me, too... a quick test to see if that's the case, select the room in the scene pane/tab and use the eye to turn it off.  Then do a render (spot render will work for this).  If everything else renders right, then do the  Cast Shadows Off or light replacement.

ttimm

Thank you both! I took the suggestion and turned off cast shadows on the room. I also disabled all the lights but I was still getting those renders with glowing fingers. That scene did have a mix of distant (which I take infinite lighting to be, correct me if I'm mistaken) and spot lights. In any case, disabling here and turning off there wasn't helping much, so I decided to go the nuclear option and start from scratch. I reloaded the room first, selected and turned off cast shadows on all of it, then loaded the character with spot lights only, zero distant lights. When I rendered with no shadows selection on the lights, the glow was there, but when I selected deep shadows for all of the lights, the glow got MUCH better (it had to be all though, even one light without shadows selected brought the glow back). I say "much" because when I tested this on the character in an empty view port without the room loaded, it was perfection. But when I tried this with the room reloaded sans cast shadows, it is in fact much better, not perfect though. I noticed that even playing with the shadow intensity, when brought down on just one of the lights, seemed to bring the glow back into play, but more gently.

So what I am in the process of doing right now is fiddling with my 3 point rig placements (with full shadow intensity but full shadow softness too) to see if perhaps the hand being where it is, it's angle, protrusion forward but adjacent to the face (these are just guessed tbh) might be affecting the scene lighting so that it looks like there is a ghost of glowing left behind. It could be that I need to play with the rig set up more. It might be a phantom limb syndrome effect so to speak as well (in that I am hypersensitive to the light the hand is catching and thinking it's a glow?).

Also, I did flip the normals on the hands to see what that would do, and it "seems" like it helped, but I really don't know if that is a misperception or not.

Anyhow, sorry for the book-length reply, but I really am grateful for the suggestions and thought I'd try to be detailed in what I did and what the effects were since you replied. I'll report back after more tinkering. Thanks!

mjc1016

Raytraced shadows would be a much better option than the DSM (deepshadowmap).  Also turning on Progressive will speed up rendering with raytraced shadows.

Also, which SSS shader AoA or UberSurface (1 or 2)?

The SSS scale/SSS shading rate may be too much.  Also velvet/translucency being 'on' can 'overdrive' the SSS amount...or seem to.

ttimm

Been away from this for a couple days, but came back to it this evening, and wanted to report back. I have been using the AoA SSS (I can't seem to locate an Ubersurface my libraries). I have forgone DSM in favor of raytracing (as a side note, both DSM and Raytracing seem to render in the same time though, progressive had been on in both cases, dunno if that applies to DSM or not however).

By translucency I assume you mean the Specc/Reflec Trans On-Off setting, which I did disable, and it seemed to help.

For velvet, I see five settings (backscatter, color, fall off, roughness and strength). I've set them all to their minimum settings since I don't know which one turns velvet off (I assume strength and/or backscatter) but it doesn't seem to have much effect though.

As an aside. I did purchase the Advanced Lights pack, and the effect was still present with those as well.

What I have noticed is two things that make this glow effect happen/get worse. Disabling or softening shadow intensity of the lights, but even more so, when the hand of the character is in contact with another skin surface, as in the snapshot above, or when the character is grasping their forearm with their hand, something like that.

If worse comes to worse and I can't alleviate it any further, at least I have isolated a few things that seem to help it, and I appreciate you all pointing those out. So it's not the end of the world if I don't figure this out, but I keep thinking to myself that I can't be the only person that has experienced this before in DAZ, and if I could understand why, it would be nice anyhow.

Again, my thanks :)

 

 

 

 

 

mjc1016

ttimm said:

 

What I have noticed is two things that make this glow effect happen/get worse. Disabling or softening shadow intensity of the lights, but even more so, when the hand of the character is in contact with another skin surface, as in the snapshot above, or when the character is grasping their forearm with their hand, something like that.

Is there something else in the scene using SSS?

If so, there's a chance that it is using the same ID...try changing the SSS Group ID.

Also what is the Shading Rate and Shading Scale (Surface parameter, not Render parameter) for the skin?