You searched for: “orthochromatic
1. In photography, maintaining natural relations of light and shade; especially, by the use of films or plates treated to give correct values to the reds, greens, blues, and yellows.
2. Having normal staining characteristics; such as, orthochromatic film, a photographic film that responds to colors in their normal brightness as seen by the eye.
3. Relating to, or producing, true tone values of light and shade in a photograph that correspond to the tones in nature.