Skin and shaders

paulawp (marahzen)

Hi, I'm still pretty much a newbie, but I'll ask this question here in this forum. This has probably been discussed to death, so I'm perfectly happy being redirected to an existing thread.  I looked, but I couldn't find it.

A year and a half ago, I started tinkering with FaceGen to convert Artbreeder portraits to use in Daz. I had encouraging early efforts when testing, but when I decided to get serious about learning to use Daz this summer, the results were terrible. After inspection, I realized that I had tested last year with G3 and the Subsurface Base Shader for skin. When I started this year, I decided to use G8.1 figures as a base, and the stuff exported out of FaceGen, used with Iray Uber, is completely wrong - very dark and red compared to the original source. I have yet to figure out why that is, because I don't see anyone else talking about having this problem with Iray Uber. Up to now, I've been working around it by simply switching skin surfaces to the Subsurface Base Shader and have had acceptable results, but I'm ready to try to do better work. It's time to figure this out.

Here is a very quickly created series of examples, all with the same default environment and lighting. I've selected "New" for a new window and loaded a basic G8.1 male figure. I then applied the textures and shape created by a FaceGen export for a G8.1 male. The first example is rendering directly from that, with Iray Uber. The result is extremely dark and reddish. Next, I converted all of the skin surfaces (arms, body, face, etc) to Subsurface Base Shader. The third is what I get if I switch the original Iray Uber skin surfaces to Daz IRay PBRSkin, which results in a similar shade as the Subsurface Base Shader but a bit less shiny. (For comparison, the image with hair is the original image from Artbreeder, which FaceGen used to create the jpgs for these surfaces.)

What's up? I see countless images in forums and in the Daz shop which are described as using Iray Uber that don't do this. Do I have something squirrelly set somewhere? Why does it do this? If I can't fix it, I'll just test further to see if Daz Iray PBRSkin shader - which I just literally discovered today - is worth switching to for this purpose, but I've seen forums in which many people prefer Iray Uber to it. Thanks!

charles

Hi,

I mainly work in the Uber Iray version. Besides just changing out the shader have you looked at the "surface" tab and taken the time to learn what the different elements do? There is a lot going on in those settings, such as your shinny and greasy look is controlled by the dual specular lobe settings.  Having a good map(s) that controls that is really important to getting a photorealistic look. There is also the Translucency Weight that mostly controls the darkness/lightness of the skin. But there's lots of other stuff that may need tweaking as well.  What skin base were you starting with just the default g8.1 or a specific character?

Keep in mind that FaceGen, and all the face transfer ones for Daz I'm aware of are pretty limited in what they can do structurally to the face. There are not enough points to really get a face exactly, it can get the jaw outline ok, nose position, mouth corners and parts of the eyes, but it's not going to really do any of the other details. You'll need to have a good libary of morphs to finish the job. I would say you could bring it into Zbrush or Blender but unless you become a PA you won't be have HD access for the finer details but can still do some pretty good tweaking without morphs in those. But morphs maybe your best bet.

 

paulawp (marahzen)

This was just the default G8.1 figure. I selected the new .jpgs created by FaceGen as the Base Value for the respective parts.

I have very minimal knowledge of what's in there on the Surfaces tab. I've spent a little time tinkering and making random changes to explore what settings do, but that's about it. I'm learning my way around from scratch. 

charles

Got ya. That's where you need to concentrate, it's the key to getting your surfaces looking how you want. You'll need to do some digging for some good threads detailing with it, or there is some good youtube videos out there.

 

charles

Actually you are in luck this just posted in the othe forum.

My Skin Tweaks for the Iray Uber Shader - Daz 3D Forums

 

paulawp (marahzen)

Thanks for your comments, I'll check into the info on the other thread. Funny that got posted literally the same day. I haven't been to that other forum where it got posted, so I wouldn't have seen that.

Regarding shaping, I have picked up a lot of morphs and can do better in that regard than this example, which is just with the FaceGen morph alone applied to a newly loaded default figure. In this thread, I was specifically trying to chase down the reason for the freakishly off skin color that always happens with Iray Uber for me.

(In fact, I have so many morphs that it's a whole other project in itself for me - a fiction writer trying to learn art, with no real background in art or human anatomy - to learn to use them. But that's a whole other subject. For that, I have tools and I get what needs to happen; it's on me to develop an eye to see what needs tweaking and know which morphs will help push in that direction.)

charles

Check your PM.