RG color models

An RG color model is a dichromatic color model represented by red and green primary colors. These can only reproduce only a fraction of the colors possible with a trichromatic color space, such as for human color vision.

The name of the model comes from the initials of the two primary colors: red and green. The model may be either additive or subtractive. Despite its shortcomings in color reproduction, these models were used in early color processes for films.