A colour picture produced by assigning a colour to a particular spectral band. Ordinarily blue is assigned to band 1 or 4 (~ 500 to 600 nm), green to band 2 or 5 (~ 600 to 700 nm), and red to band 3 (~ 700 nm to 1 µm) or 7 (~ 800 nm to 1. 1 µm), to form a picture closely approximating a color-infrared photograph.