https://docs.blender.org/manual/en/latest/render/color_management.html
Color management is important to create renders and assets that are physically accurate and look great on multiple display devices. It is used both to ensure all parts of the pipeline interpret colors correctly, and to make artistic changes like exposure and color grading.
Different views and exposures of the same render.
Blender’s color management is based on the OpenColorIO library. By using the same OpenColorIO configuration in multiple applications, the same color spaces and transforms will be available for consistent results.
For correct results, different Color Spaces are needed for rendering, display and storage of images. Rendering and compositing is best done in scene linear color space, which corresponds more closely to nature, and makes computations more physically accurate.
An example of a linear workflow.
If the colors are linear, it means that if in reality, we double the number of photons, the color values are also doubled. Put another way, if we have two photos/renders each with one of two lights on, and add those images together, the result would be the same as a render/photo with both lights on. It follows that such a radiometrically linear space is best for photorealistic rendering and compositing.
However, these values do not directly correspond to human perception or the way display devices work. and image files are often stored in different color spaces. So we have to take care to do the right conversion into and out of this scene linear color space.
Transforming scene linear colors to display involves both technical and artistic choices.
Correct display of renders requires a conversion to the display device color space. A computer monitor works differently from a digital cinema projector or HDTV, and so needs a different conversion.
There is also an artistic choice to be made. Partially that is because display devices cannot display the full spectrum of colors and only have limited brightness, so we can squeeze the colors to fit in the gamut of the device. Besides that, it can also be useful to give the renders a particular look, e.g. as if they have been printed on real camera film. The default Filmic transform does this.
Conversion from linear to display device space.
