A second common confusion about screen gain arises for grey colored screens. If a screen material looks grey on casual examination then its "total" reflectance is much less than 1. However, the grey screen can have measured gain of 1 or even much greater than 1. The "geometric" behavior of a grey screen is different from that of a white screen of identical gain. Therefore, since geometry is important in screen applications, screen materials should be at least specified by their gain and their total reflectance. Instead of total reflectance, "geometric gain" (equal to the gain divided by the total reflectance) can be the second specification.