Fiddling with Iray skin settings...

Rareth

interior scene, IBL coming in the sliding glass door, 5000 iterations, I think it needs to go longer.

ZarconDeeGrissom

8eos8 said:

So I finally figured out how to use SSS Reflectance Tint properly without making Olympia look like a space alien (the suggested value in the docs seems to be way off...) and I redid my skin setup based on some recent suggestions in the Iray render thread. The main change here was to set the gamma of the skin textures in Gimp to 2.2 (making them a lot lighter) and move them from Base Color to Translucency Color, and to put desaturated versions of the textures in Base Color. I also tried out the Macro skin textures (bottom 2 images), setting them up the same way. I wasn't able to use the SSS maps that come with them though, because setting the texture on Transmitted Color doesn't have any visible effect, only changing its color works (guess I should file a bug...) Still, they look very nice to me using just the diffuse and normal maps.

Base Color = desaturated textures + gray (HSV 0/0/60) (can use lighter gray for paler skin; or white if using albedo textures for translucency)
Translucency Weight = 0.8
Base Color Effect = Scatter & Transmit
Translucency Color = white + diffuse textures (set gamma to 2.2) (update: or use albedo textures)
SSS Reflectance Tint = HSV 180/85/120 (this should be a dull greenish-gray, like the color of a corpse)

Glossy Layered Weight = 0.2
Glossy Color = white (no maps)
Glossy Reflectivity = 0.35
Glossy Roughness = no maps + 0.3, or inverted bump maps + 0.6-0.8 (this controls the wetness of the skin; didn't use Top Coat at all except on the lips)
Refraction Index = 1.4
Base Bump = 5 (no maps + 0 if using Macro skin)

Transmitted Measurement Distance = 2.5 (controls overall thickness of skin, affects translucency of ears and nose)
Transmitted Color = no map + HSV 35/180/160 (Macro) or 20/191/162 (Olympia) (this controls the base skin tone, adjust as needed)
Scattering Measurement Distance = 0.1-0.2 (controls the amount of translucency and SSS on the skin surface, you don't want this too large)
SSS Amount = 0.9-1.0 (I didn't like smaller values for this, looked too much like a silicone doll)
SSS Direction = -0.5
(update: now I prefer SSS Amount = 0.8 and Direction = -0.9)

Now that is cool. All I need to do now, is translate that to GIMP :blank: and learn how to actually use GIMP :-/

The renders look good by the way. :coolsmile:

Takeo.Kensei

Wrong thread sorry

Oso3D

Based on comments by Mec4D on the other Iray thread, my current experiment:

Using Skin Builder to generate a skin with no lighting information baked in, and very light colored (basically close to white (Pale, in Skin Builder)).

Then add details, particularly bump and displacement, in Skin Overlay (current experiment, adding freckles, vascularity, some other displacement stuff).

For the actual skin, use a slightly yellow-gray at about 160 brightness, .5 Translucency weight 255 red. (I might also try using a weight map of the diffuse map inverted, so that skin coloration, like freckles and nipples, are less translucent, but we'll see).

SSS: 2 trans distance, .5 SSS distance, .5 SSS amount, -.9 direction

At least so far, ending up with a really luminous, soft, beautiful skin (I have a bright window behind providing a huge amount of backlight)

Also will try with light toward the front and NOT backlit, to see how the skin looks under more normal circumstances.

It looks a LITTLE more pink than I'd like -- what would be ideal is a translucency weight map that compensated for body thickness. I'm wondering if I should use SSS more than translucence for that.

Timbales

Thank you for sharing your settings, it really helped me get a handle on using Iray.

Oso3D

Oh, I never posted my image... the sassy redhead uses the skin settings I mentioned (though I tweaked it a little to use PBR Glossiness/Specular, it's mostly the same).

As a VERY light skinned figure, the skin maps ended up REALLY light. One thing I did to help make the freckles stand out was apply the brightening/desaturation, and THEN add freckles with skin overlay. Really made them stand out (I wouldn't do that for someone less fair-skinned).
I also added the eyebrows after the brightening/desaturation, since they need to stand out (and aren't skin!)

Here are two face maps I've done for comparison... the first is the redhead's diffuse, the second is another character's more normal diffuse.

Again, my approach is: Contrast +40, Saturation 50%.
Ideally you'd pull skin coloration away from lighting effects, but I don't really see a viable way to do that with regular skin sets.

I generally prefer to end up with too light skin, provided you aren't compressing or loosing color information, since you can add base color to tweak as needed.
For my redhead, for example, I ended up a 200 gray to dim the skin a little bit, because that skin map ended up too bright.

(My real skin maps are 4096x4096 PNG files, these are just smaller snapshots for space considerations)

(Images were removed as they were full texture images.)

Jimbow

If you fancy trying converting your diffuse textures to albedo pbr maps and have Photoshop CS4, here's a method that I've been using for my latest skin setups which are mostly Base Colour Scatter&Transmit; these days, heavily using translucency/subsurface 'meat' maps. Even though there's no save command in the action, be sure to backup your original textures. You'll need to modify the luminance of selected areas (lips and nipples mostly), but it works great so far for extracting base pigment/colour information from the traditional diffuse texture. Used on all of the skin textures for the figure shown:

Oso3D

Are you using a Vascularity bundle there?

Jimbow

timmins.william said:

Are you using a Vascularity bundle there?

I posted it elsewhere weeks ago, but here's the link again.

https://amarijun.wordpress.com/2014/04/13/genesisgenesis2victoria4-blood-vessel-textures/

I also added a lot to them using a procedural vein setup I have for Softimage Mental Ray. I then took the M4 muscle maps I had, blurred and did more stuff to them in PS to make the cartilage look like fatty tissue and to get rid of the dark crevices, and added my vein maps on top. Then I mixed the new "pbr albedo" maps 50% on top, the principle being that skin has a thickness and will contribute to the subsurface shading.

I'll see if amarijun wants the new maps once I'm happy with the setup. I have to fix some seams as I'm using Softimage ultimapper to make all textures fit to the BaseMale UV space, and some seams are showing now and again, but they really show up with displacement using Base Colour Scatter&Transmit;. However, if I add a skeleton or internals the seams seem to disappear. I'll render a V6 using exactly the same skin setup but rimlit and post it tomorrow.

It's actually quite shocking how well seemingly flat, featureless, de-photo'd textures work in iray. Another test is at Devious Fart using the aforementioned technique on the Stonemason ruins textures and the figure textures:

http://tarbicus.deviantart.com/art/irayOrcs-JimBowers2015-529515429

Richard Haseltine

I'm not sure what you mean by the new maps, but just to dot the Is and cross the Ts you wouldn't be able to share something that included the M4 Muscle maps.

Jimbow

Richard Haseltine said:

I'm not sure what you mean by the new maps, but just to dot the Is and cross the Ts you wouldn't be able to share something that included the M4 Muscle maps.

Good point and thanks for the slap on the head. They'd probably work fine without the muscle maps as they really do turn out incredibly indistinct and I'm probably just being anal about the internal meat. Besides, I can make my own if I must.

Oso3D

What's the high pass doing? Is that a sharpen effect?

(I'm using Paint.net, and I have a high pass filter, but it has more options to work out)

Cris Palomino

Please bear in mind, as Richard noted above, if a texture is made partially or wholly by modifying another texture to which you don't have the rights (a DAZ or PA character map, for example) you may not share it - that includes posting it in the forum.

Oso3D

The images I showed were very low resolution and incomplete, only meant to explain what I was doing.

I can understand that that may not matter, but I'd like it to be noted that I wasn't sharing IP I don't own in any meaningful sense.

Oso3D

Meh. Where all of this really falls apart is trying to make decent dark skin... because then the highlights are REALLY over the top, and you can't just grab light skin and darken it, because the patterns are different.

(I'm trying to play with Benjamin and... ugh, it's a cool skin but there is a LOAD of lighting baked in, and there's only a bump map to drive other elements)

Jimbow

timmins.william said:

What's the high pass doing?

It's generally used to sharpen images.

http://www.photoshopessentials.com/photo-editing/sharpen-high-pass/

If you use it as a luminosity blend layer on the original texture, it gives you good colour information to play with. I don't know paint.net so can't go beyond that.

Jimbow

Cris Palomino said:

Please bear in mind, as Richard noted above, if a texture is made partially or wholly by modifying another texture to which you don't have the rights (a DAZ or PA character map, for example) you may not share it - that includes posting it in the forum.

Just as well I didn't post it in the forum. It's okay folks, I have no intention of disseminating copyrighted work. No need to police anyone ;)

Oso3D

Ah, ok. Yeah, I've tried to massage out color information before, the problem is that, say, dark skin with a highlight, the highlight washes out the color. So to speak.

Consider this (real world image and not IP): http://phillips.blogs.com/.a/6a00d834515c6d69e2010534e2ebaf970c-320wi

That forehead? You've lost the color. But there are little details you still want.

I expect, going forward, that we'll see more skins without lighting baked in.

Jimbow

Don't talk about it, just do it. This is not finished shading I'm showing ;) I'm not selling anything.

Oso3D

I don't have the skill to do it... it'd require good photography and a subject, or good painting, and I'm not good at either.

Jimbow

Just did the action on the Ryze face texture. Looks okay using an exposure filter to take the original underlying texture down a stop or two. You'd also need to take down the subsurface textures I imagine.

Jimbow

timmins.william said:

I don't have the skill to do it

I'm sure you have the tools to do it. High pass is just high pass. It doesn't matter what the app is. I think you need surface blur mode.

Jimbow

Here's an incomplete render of V6 using the same skin as before.

Makaula Nakae

This is how I did...

Iray Uber Base to convert first.

Remove all Specular maps, all tinted colors change to WHITE

Base mixing: PBR Specular/Glossiness

Base Color: Skin Map + White

Translucency Weight : Skin Map + White+ 1.00

Glossy Layered Weight: 0.10 <--- this changes skin tone to whitely</p>

Glossy Color: NO MAP + White

Glossiness: 0.75

Refraction Index: 1.44

Base Bump: 2.0 (Lip: 1.2)

Top Coat Weight: 0.20 <---- this changes coating thickness</p>

Top Coat Color: White (NO Map)

Top Coat Glossiness: 1.00

Top Coat Layering Mode: Fresnel

Top Coat Bump: 1.20

Thin Walled: OFF

Transmitted Color: Skin Map + White

I did many of M$ skins and M5, M6 skins, also G2 Female Base, its worked pretty well.

Thank you for reading. :)

Jimbow

Bear in mind that most, if not all, commercial skin textures have colour information in the highlights, otherwise they'd be next to pointless for shaders in renderers like 3Delight or Mental Ray. My "pbr albedo" method isn't perfect by any means, but it gives me a good headstart and very quickly in one click of a saved action.

j cade

Jimbow said:

Bear in mind that most, if not all, commercial skin textures have colour information in the highlights, otherwise they'd be next to pointless for shaders in renderers like 3Delight or Mental Ray. My "pbr albedo" method isn't perfect by any means, but it gives me a good headstart and very quickly in one click of a saved action.

Most of the -Yannek- textures, which include many of the Daz People are pretty close to Albedo textures. If you take a look at S6's or even Giselle's textures there's nearly no baked in spec; even the old gen4 elite textures hold up pretty well

j cade

Oh! I've also thoroughly updated my current skin settings after reading through the various Iray threads. Rendered with the ubiquitous pixar hdr. The skin could use more eyepopping SSS, although it is more noticeable in my standard studio lighting setup. The main focus here was the spec; most of the spec comes from the top coat this enabled me to use a tiling bump texture in the top coat bump in addition to the standard bump an normal maps. I then set the tiling higher for the limbs and torso than the face which helps to eliminate the most obvious sign that the face is higher res than the rest of the body.

Oso3D

Now that I realize you can tile stuff independently (from main thread)... that opens up a LOT of interesting options, like this one. Cool!

Jimbow

Kamion99 said:

Most of the -Yannek- textures, which include many of the Daz People are pretty close to Albedo textures. If you take a look at S6's or even Giselle's textures there's nearly no baked in spec; even the old gen4 elite textures hold up pretty well

As I've not seen them I wouldn't know, but my idea of an albedo texture is in the middle of the 4th row of images by Dan Roarty:

http://www.cgmeetup.net/home/create-realistic-3d-portraits-dan-roarty/

8eos8

Jimbow said:

If you fancy trying converting your diffuse textures to albedo pbr maps and have Photoshop CS4, here's a method that I've been using for my latest skin setups which are mostly Base Colour Scatter&Transmit; these days, heavily using translucency/subsurface 'meat' maps. Even though there's no save command in the action, be sure to backup your original textures. You'll need to modify the luminance of selected areas (lips and nipples mostly), but it works great so far for extracting base pigment/colour information from the traditional diffuse texture.

Unfortunately Gimp doesn't have a high-pass filter or the luminosity blend mode, but after reading this I came up with this procedure:

1. Copy the background layer
2. Colors > Desaturate and pick Luminosity
3. Copy the desaturated layer
4. Filters > Blur > Gaussian Blur, use a radius of 25px
5. Set the blend mode to Grain Extract and merge down the two grayscale layers
6. Set the blend mode to Value on the new layer, set opacity to 70% and merge down

I also found a plugin for color/frequency seperation, that would be another way to do it.