How can GI intensity be reduced?

Hello, developers:
I used cycles to render characters a lot, but I often felt that the GI reflected light of the rendered images was always too strong(even if set one bounces), and I couldn’t find any parameters to set the GI intensity.
I am wondering whether a parameter called GI intensity can be added to the attribute of cycles so that we can define the GI intensity to achieve the ideal effect.

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Yeah,I also hope that developers can figure it out!Anyway, your character render is excellent!

What is it reflecting off, how is your character lit? I think you could simply add a dark or black floor in your case.

You may want to try posting in the lighting category. GI is a natural consequence of pathtracing, so you should try adjusting either your materials or your lighting/environment. This little rim light on the chin is probably just the environment reflecting off the skin. I assume the set in your reference image had a darker ground that didn’t give off as much light.

I agree with Adriscus: GI intensity wouldn’t alleviate that bright spot but would make it less bright. Better you check for what might be bouncing that light up and into your characters face. Looks like the ground.
Check that your ground material isn’t highly specular.
Very nice render.
Robert

I used black material for the floor, so the light reflected from the face should come from the body.
It seems that normal materials have the same reflective intensity as SSS materials, the reality is that SSS should reflect less light because some of the light is absorbed internally.

But it’s strange, if I lift the black ground up to the hip of model, the light reflected on my face will be darker, and the higher I rise, the darker it will be.

Now I can only use composite lighting to make the GI darker.

Can you show your lighting setup? Maybe you just have to increase the size of your ground.

There is no light coming from the ground, but GI still reflects from below, no HDR or world is used ,Maybe I’ve overlaid two gloss to material, making it reflect a little too much light, but that’s what the material needs, and the ground size cannot be infinite, otherwise the background of the render image will have some black ground.

You can set the ground to not show up on camera.

Is the model the only thing in the scene? Does she have clothes? It also looks like the lights in your scene are very strong compared to the reference, so more bounce is expected. It’s hard to troubleshoot without all the information.

This is interesting. I wonder if that’s due to a bad implementation of the shader. What SSS method are you using?

I don’t mean to say dirty words, I think the reflection of the light coming from the chest refers to her light-colored skin, it might happen.

I uploaded this blend file here:
GI test(female)0.zip (1.1 MB)

I use a very simple material:

you have created a very good skin node, this is the most realistic skin shader I ever seen on the blender forum.

it’s time for me to study the skin shaders you’ve made XD

That add node is problematic as I see it.


It is as others have said: something is causing reflections.
With the add node I think it was pushing things out of numerical bounds.

thank you for the reply, if the glossy node can’t be linked to the add node,than what is the useness of add node?

Not saying it can’t; saying that it is unhelpful for your needs.
If you play with the fac slider, you can see the bright spot come back under the chin. With that add node as you had it, the mix was doing nothing and the add was not providing anything to the scene.
What did you intend the Add to do when you put it there? Add what to what?

I just want to add extra highlights without changing the old shader color.If glossy link to a blend node, it will darken the old shader around the area of weaker glossy.

The add shader node is not physically correct.

I try to use the material to simulate the color gradient of this kind of bright dark relationship, dark (red) → grey (yellow) → bright (white), using the default material is not able to do this effect. Can only use different color overlay, but the effect is not too ideal.
I hope that there is a material that can have color gradient according to the intensity of the glossy.

color gradient.blend (1.4 MB)

Kind of hard for us to follow along in Chinese :sweat_smile: But at least now you know it’s the shader, not the GI. I think you can find some really good kin shaders online for free. Are those not useful to you?

Hmm, now its getting fun!
I’m a bit rusty on translating Chinese; the dictionary is…to be learned and so different.

Would you mind translating the labels on those nodes? You help us, we can better help u.