Dark colors in PBR range look too bright

[Alec]

Hi all,

I’m working on a diorama, and I need to use “dark” colors, like black ( or almot ), or navy blue )

It’s not metallic matter, and I tried to keep in mind the PBR values, and PBR range.

However, even I go quite low in PBR values, I get the feeling it’s still bright. I want a black color, and it’s juste " dark grey " in UE5.

You can see 2 screens. First is black for me, but not PBR accurate ( very low value )

Second is ok with PBR value. Very very low, but it’s in the range. However, for me it’s more a grey, than a black color…

My question is : how can I have a black ( not a real black, because it’s not in PBR range ), but at least, feeling of black color, with PBR values ?

When you add metallic values in your shader, it’s more black, and more like that I need, however, it’s not correct with PBR chart

Have you an idea ?

thanks

[BananableOffense]

Reducing the specular value will allow you to achieve a darker black.

[Alec]

Yes, but if you need something not too reflective ? :d

[Alec]

another example :
Grey value is at 0.023, it’s very very low, and see the render… ( in the middle of the props )

[DragonRelt]

You need to go into the material instance of the thing your trying to adjust and set it in there, then you can mess with the specular and the roughness and the metallic mat. This is the only way you can adjust this without the shine that your getting. It is a roughness modifier that your looking for in general though, but with the other two you can make loads of colors in unreal and including better texture’s all around

[Alec]

Hum, of course I can play with sliders, but my goal is to stay in appropriate PBR values.

I can get a darker color, for example with metallic, or slide down bellow 0.02 in gray value, but it’s incorrect with PBR values.

[BananableOffense]

I think this is probably an issue with color space (sRGB vs Linear).

vs

Notice how the converted color gradient seems much more evenly distributed while the other seems heavily skewed towards light colors.

In other words, 0.023 isn’t as dark as you expect it to be due to the color space you are using.

Here is 0.023 vs 0.023 w/conversion vs true black

And you can get lots of different shininess levels
glossy

matte

high gloss

All of this was achieved only adjusting diffuse, specular and roughness.

Diffuse defines the amount of diffuse light being reflected.
Specular defines the amount of specular light being reflected.
If you have a low diffuse, but a high specular, the object will still reflect lots of specular light and end up looking gray.

Roughness of course determines how scattered the reflected light is.

PBR is not a perfect model so if you need to break the rules to get the desired effect, you should.

You may also consider enabling the new substrate system, as it allows for more complex materials - including more sophisticated secular.

[Alec]

Thank dude

It’s interesting, I tried to use a sRGB Linear node, and yes, I’ve black color.
However,I guess it’s a different way to have a darker value, and you are probably out of PBR range

it’s exactly the same probleme here : Darker blacks using PBR Metal/Rough? — polycount

Some people think it’s the lighting…

[BananableOffense]

Yes lighting is a significant factor. If an object appears too bright, really only four things are possible:

1. It is reflecting too much diffuse light
2. It is reflecting too much specular light
3. There is too much light in the scene
4. The object is self-emissive

But if that isn’t good enough - There are no PBR police. If you need to go out of range to achieve a desired result - then do it. The flaw with obsessing over “PBR range” is that real time models such as this are not actually perfectly physically accurate anyway. There is little point banging your head against a wall because you need something to be a bit darker. There is a reason it is called 3D Art. Sometimes art direction (ie “Make this darker”) is more important that self imposed rules.