Vray Meta Image Node Color Space

[creac]

Hello,
Is that correct to say
Inverse Gamma for Color Space with .exr for diffuse map
None for Color Space with .png for diffuse map

Thx

[chakarov]

Hi creac ,

Color Space – Specifies the type of color space used by the bitmap.

Linear –The bitmap data is already in physical linear space, so no correction required and none is performed.
Gamma Corrected – The bitmap data is gamma corrected with the specified gamma value specified by the Texture input gamma attribute, so V-Ray needs to remove this gamma correction for rendering.
sRGB –The bitmap data is in the sRGB color space, so V-Ray needs to convert it to linear physical space for rendering.

in "Color Space" of V-Ray ImageFile you should specify the space your image file is saved. For example most likely your exr file is linear /gama 1/ so you should set "color space" to none. But jpg, png are in sRGB , so "color space" should be "sRGB".

In general you can use these two simple rules to set "color space" parameter for images:

"color" parameters like diffuse,reflection,refraction...(green material inputs) will be converted to linear space during render that is why this parameter should be set correctly for them.
"value" parametrs like glossiness, opacity, metalness ...(blue material inputs) should be set to "None".

Bump maps is the exception of this rules, it should be set to "None".

Of course if you know that textures files are saved in other gamma , then should change "color space" accordingly. But in most cases hdr,exr are linear /none or inverse gamm = 1 /; jpg,png are insRGB.