Orange (colour) Orange (colour) Orange is the colour between yellow and red on the spectrum of visible light. Human eyes perceive orange when observing light with a dominant wavelength between roughly 585 and 620 nanometres. In painting and traditional colour theory, it is a secondary colour of pigments, created by mixing yellow and red. It is named after the fruit of the same name. The orange colour of carrots, pumpkins, sweet potatoes, oranges, and many other fruits and vegetables comes from carotenes, a type of photosynthetic pigment. These pigments convert the light energy that the plants absorb from the sun into chemical
Colour cast Colour cast A colour cast is a tint of a particular colour, usually unwanted, which affects the whole, or portion, of a photographic image evenly. Certain types of light can cause film and digital cameras to have a colour cast. Illuminating a subject with light sources of different colour temperatures will usually cause colour cast problems in the shadows. In general, the human eye does not notice the unnatural colour, because our eyes and brains adjust and compensate for different types of light in ways that cameras cannot. In film, colour casts can also be caused by problems in development.