These charts have an overall size of 12.5" x 10". Original standard in U.S. for setting light response characteristics of TV cameras. Use for adjusting dynamic range and for balancing R, G and B channels for correct color reproduction. Chart consists of 2 sets of 9 neutral grey patches on a uniform grey background. Reflectances range from 3% to 60% in accordance with RS-170 (Logarithmic 2 law = approx. 1/2 f/stop per step). Dead black patch (R less than 0.5%) establishes accurate black level and for use in setting flare compensation.