additive color adobe rgb color space adobe wide gamut rgb color space alvy ray smith black blue budapest university of technology and economics cmyk color model color color blindness color space color television color temperature color tool color vision color wheel coloroid cyan euclidean space evolution ewald hering gamut green hermann von helmholtz hexachrome international commission on illumination kruithof curve lms color space list of color spaces and their uses magenta munsell color system ntsc natural color system osa-ucs opponent process opsin optical society of america pal pantone primary color prophoto rgb color space projective plane rgb color model rgb color space ryb color model red secam srgb scrgb color space subtractive color vertebrate xvycc ycbcr ydbdr yiq ypbpr yuv yellow