How does VRay prevent texture discoloration in the ACES color space

[123456_]

I don't know if my description is clear, just like in the picture. I set the color node in c4d2025 according to the picture, and it shows as 0.0.255 in VFB. But if I use a blue map of 0.0.255, then VFB shows 0.0.210. Is there any way to make the map also display as 0.0.255? I guess we may need to use ocio nodes? How should it be set up.

[wolfgang_himmelfarb]

I'm sure someone form chaos can give you a more complete picture but Acescg requires that you explicitly tell the engine what color space your maps need to be transformed from, in your case its going to be sRgb. If you want your colors interpreted "correctly" by the render engine you will need a bitmap node which you set to sRgb for the transfer and primaries - this is of course only if your textures were made in sRgb color space, which I assume they were. You can output Acescg maps form Substance and in that case you set them as Auto in the bitmap node. With the correct transform and primaries set, the render engine knows what color space your maps were created in and can interpret them correctly, at render time. It's not good enough to only transform at the end, in the VFB. You have to make sure all your incoming maps, pre-render is also transformed into Acescg.... including other color maps like hdri and translucency.

Maybe more important to understand is that Acescg is not really meant for situation that require high color accuracy like logos or for certain types of graphics. Acescg is meant to emulate color falloff similarly to cinema film and for renders to behave in post more like film emulsion. Hope that helps - Acescg takes some time to get used to but you'll find the results much better from the beginning and working with Acescg is much more satisfying to work on in post.

[123456_]

I'm sure someone form chaos can give you a more complete picture but Acescg requires that you explicitly tell the engine what color space your maps need to be transformed from, in your case its going to be sRgb. If you want your colors interpreted "correctly" by the render engine you will need a bitmap node which you set to sRgb for the transfer and primaries - this is of course only if your textures were made in sRgb color space, which I assume they were. You can output Acescg maps form Substance and in that case you set them as Auto in the bitmap node. With the correct transform and primaries set, the render engine knows what color space your maps were created in and can interpret them correctly, at render time. It's not good enough to only transform at the end, in the VFB. You have to make sure all your incoming maps, pre-render is also transformed into Acescg.... including other color maps like hdri and translucency.

Maybe more important to understand is that Acescg is not really meant for situation that require high color accuracy like logos or for certain types of graphics. Acescg is meant to emulate color falloff similarly to cinema film and for renders to behave in post more like film emulsion. Hope that helps - Acescg takes some time to get used to but you'll find the results much better from the beginning and working with Acescg is much more satisfying to work on in post.

Thank you for your enthusiastic reply. I was just asking if there is a way to prevent the texture from changing color, such as redshift, which defaults to the aces color space, but following the settings in the picture can ensure that the texture does not change color. I think VRay also has a way to do this

[wolfgang_himmelfarb]

redshift, which defaults to the aces color space, but following the settings in the picture can ensure that the texture does not change color.

ah, I see what you mean now. You already set your transfer and primaries to srgb. could be a bug honestly.

[piotrus3333]

I'm sure someone form chaos can give you a more complete picture but Acescg requires that you explicitly tell the engine what color space your maps need to be transformed from, in your case its going to be sRgb. If you want your colors interpreted "correctly" by the render engine you will need a bitmap node which you set to sRgb for the transfer and primaries - this is of course only if your textures were made in sRgb color space, which I assume they were. You can output Acescg maps form Substance and in that case you set them as Auto in the bitmap node. With the correct transform and primaries set, the render engine knows what color space your maps were created in and can interpret them correctly, at render time. It's not good enough to only transform at the end, in the VFB. You have to make sure all your incoming maps, pre-render is also transformed into Acescg.... including other color maps like hdri and translucency.

Maybe more important to understand is that Acescg is not really meant for situation that require high color accuracy like logos or for certain types of graphics. Acescg is meant to emulate color falloff similarly to cinema film and for renders to behave in post more like film emulsion. Hope that helps - Acescg takes some time to get used to but you'll find the results much better from the beginning and working with Acescg is much more satisfying to work on in post.

ACEScg IS meant for achieving high colour accuracy as it can describe all the real-life colours that BT.709 can not. you are confusing colour space with display transform that indeed may shift hues in undesirable ways on your display. in that case just use different display transform.

[wolfgang_himmelfarb]

ACEScg IS meant for achieving high colour accuracy as it can describe all the real-life colours that BT.709 can not. you are confusing colour space with display transform that indeed may shift hues in undesirable ways on your display. in that case just use different display transform.

This isnt my post, I'm just reporting what's common among motion designers who use Cinema and RS when company colors need match from shot to shot for example. But my bad maybe I'm wrong. Anyhow, youre the aces guy so ill let you address the original post. I'm honestly not trying to get involved.

[boyan]

I don't know if my description is clear, just like in the picture. I set the color node in c4d2025 according to the picture, and it shows as 0.0.255 in VFB. But if I use a blue map of 0.0.255, then VFB shows 0.0.210. Is there any way to make the map also display as 0.0.255? I guess we may need to use ocio nodes? How should it be set up.

Ni Hao, 12345,

Thank you for the question. I will try to explain with your examples. In the first image, ACES, you reach the maximum RGB value (you can check this in your VFB setting). The real color in ACES space as value is more than 1, but because you used sRGB, you got the maximum. This is not the case in the second image when you use sRGB, and you can see the actual value of sRGB - 0,0,210. Check it if that is the case. What value will you get if you switch to RAW in VFB ?

[123456_]

Ni Hao, 12345,

Thank you for the question. I will try to explain with your examples. In the first image, ACES, you reach the maximum RGB value (you can check this in your VFB setting). The real color in ACES space as value is more than 1, but because you used sRGB, you got the maximum. This is not the case in the second image when you use sRGB, and you can see the actual value of sRGB - 0,0,210. Check it if that is the case. What value will you get if you switch to RAW in VFB ?

So how should I handle the texture to make the final color display as 0.0.255? In Redshift, I only need to modify the texture color space to the option in the image to display the effect of 0.0.255.

[boyan]

So how should I handle the texture to make the final color display as 0.0.255? In Redshift, I only need to modify the texture color space to the option in the image to display the effect of 0.0.255.

Mya, I suggest trying the V-Ray OCIO texture. The OCIO file is required. From there, you can change the input and output file type.

[123456_]

Mya, I suggest trying the V-Ray OCIO texture. The OCIO file is required. From there, you can change the input and output file type.

How should I implement it? I am currently using the OCIO file that comes with C4D, and it seems that I cannot achieve the redshift effect

[boyan]

How should I implement it? I am currently using the OCIO file that comes with C4D, and it seems that I cannot achieve the redshift effect

Could you please check the attached file?

[123456_]

Could you please check the attached file?

It seems to have no effect on texture mapping. Can you try using my 0.0.255 texture map

[boyan]

[QUOTE=123456_;n1217166]

It seems to have no effect on texture mapping. Can you try using my 0.0.255 texture map [/QUOTE

It seems something is wrong I guess in my side, check it once again

[123456_]

[QUOTE=boyan;n1217168]

It seems to have no effect on texture mapping. Can you try using my 0.0.255 texture map [/QUOTE

It seems something is wrong I guess in my side, check it once again

This is how Redshift achieves the effect I need

[boyan]

[QUOTE=123456_;n1217174]

This is how Redshift achieves the effect I need

Like this setup, maybe?