When you add an image to a scene, you need to specify the color space that it uses so that the colors can be properly converted to the working space used for rendering. This includes images used as 2D File textures (see Map a 2D or 3D texture) as well as image planes (see Image planes).
New image nodes in the scene initially use the color space set by Default Input Color Space in the Color Management preferences, but you can change each node individually by manually setting Color Space in its attributes.
You should always use the correct color space for each image. If you are not sure of the color space that an image uses, you should try to find out for certain or else the results may be incorrect. However, here are some general guidelines:
- Most digital paintings and photos that are used to represent color values should generally be set to sRGB. This includes PNG images, as well as JPEG, Targa (.tga), 8 and 16-bit TIFF, and many other integer-encoded formats. Note that when images set to sRGB are converted to the rendering space, the sRGB gamma encoding gets removed but no inverse tone map is applied.
- EXR files and floating-point TIFF files are almost always scene-linear. There is a very good chance that they use scene-linear Rec 709/sRGB, but if the result looks incorrect then you can try ACES or one of the other scene-linear options.
- Images that represent non-color data such as normal maps should not have any color management applied. Set the input color space to Raw.
- Image planes used as backplates might use one of several color spaces. Scanned film plates typically use Log film scan (ADX), Log-to-Lin (cineon), or Log-to-Lin (jzp). Footage from a digital cinema camera should use the option corresponding to the specific type of camera, such as ARRI LogC or Sony SLog2.
See also List of input color spaces.