How do you light up dark skin in iray?

Nosiferret

I am having a witch of a time lighting up a fantasy dark skin texture in iray. I have not seen any images where figures like dark elves and the like have been rendered in Iray. The things I've tried just washes out the eyes, or other props around the figure. The skins I have, it seems the face is always dark, I can get the body to show itself but it's texture is lighter than I want, and the face is always shadowed. When rendered in 3dlight, it renders perfectly with just advance ambient light added to the scene, where in Iray I've loaded it up with mesh lights all over the place and still can't get the figure to light up. So is Iray just for normal skin and nothing fancy like super dark skins?

What lights in Studio work with Iray? None of the create a light line up works in my scenes with Iray. I can put a point light right on the figures face with the fantasy texture and it doesn't do a damn thing. 

Granted, I'm a light newb, so there is a 99% chance I've screwed something up or not doing it right...but on one hand I want to just give up and call it quits but on the other I'm turning into a rottweiler with it and refusing to let go. 

Oso3D

One thing you might want to do is go into Tone Mapping and set 'crush blacks' to 0. It tends to flatten dark colors which, obviously, you want to avoid.

 

fastbike1

Here's a couple fo quick renders. I'm not seeing problems. Lighting is brighter in the blue render but skin tones are still good on the black render.

Obvious guesses:

1. You're not actually using Iray (it is the default in Studio 4.8 64 bit). If you're not running 64 bit, you don't get Iray/

2. Not enough light. The standard spotlights work fine. Forget most of what you know about 3Delight lighting. Iray is real world lighting.

3. Haven't used IRay shaders for the skin.

4. Finally, dark skin is harder to render or photograph without plenty of light.

Nosiferret

fastbike1 said:

 

Here's a couple fo quick renders. I'm not seeing problems. Lighting is brighter in the blue render but skin tones are still good on the black render.

Obvious guesses:

1. You're not actually using Iray (it is the default in Studio 4.8 64 bit). If you're not running 64 bit, you don't get Iray/

2. Not enough light. The standard spotlights work fine. Forget most of what you know about 3Delight lighting. Iray is real world lighting.

3. Haven't used IRay shaders for the skin.

4. Finally, dark skin is harder to render or photograph without plenty of light.

What was your light set up for the images? I am using the 64 bit, I had like 3 mesh lights up and they did not put a dent in the texture. So you did not convert your texture skin over to the Iray skin shader? I'll have to check that out and see what happens. I thought you needed the shader for iray to render properly? 

 

timmins.william said:

One thing you might want to do is go into Tone Mapping and set 'crush blacks' to 0. It tends to flatten dark colors which, obviously, you want to avoid.

 

Thank you Timmins, I will check that out.It did some changes to the texture, and I played with some of the other settings in there Gamma etc, while I rendered just using the Environment settings for iray, I deleted all my lights and mesh lights and turned the figure towards the direction of the environment light...Granted, there were no other lights in the scene, and I was just testing the various settings in Tone Mapping and then Studio crashed on me...so I don't even think it's saved anything...oh well, not a biggie I'm just trying to figure this stuff out. 

Fastbike...did you use the iray uber shader on the skin? Or any other iray shader on the skin? Or just what would have been a 3dlight skin texture in iray? 

thanks guys :) 

fastbike1

My renders both use the default Genesis 2 Iray optimized skin shader. I don't use mesh lights for general lighting as they as detrimental to render speed. The photometric spotlights in Studio's Iray implementation can do everything a mesh light can do since they allow geomrtry (e.g. a softbox). In these renders the main spots has an 80 cm spherical geometry although a rectangle or disk of the same size would work as well. I have also applied HDRI environmental lighting (Sveva Iray Intensity at Rendo).

Each render has a photometric spot in front and two photometric spot rims. The blue Elf has the front spot at 250000 lumens and iso at 200. The black elf has the front spot at 200000 lumens and iso at 100. As stated I used the default G2F Iray skin shader. The armor uses Daz Iray uber shader and the hair shader is Slosh's UHT.

I've also attached a render with the studio HDRI only. As you can see, it's not enough light for the character, rather more of a general background light. Think of it as general overhead lighting in a studio where you would use softboxes and relfectors for your subject.

In both of the previous renders the spotlight is above and in fornt of the figure, angled down with the beam narrowed to primarily get the head and torso. The lighting is exactly what you would expect in that case.