SUBTRACTIVE COLOUR MIXING The subtractive model relates to all of the colours we see of non lightemissive objects , such as textiles , paints , inks , etc . - basically any colour that you see on a physical surface . Subtractive colours are those which reflect less light when they are mixed together . Subtractive colours begin as white . With each mix , we subtract more and more light - ultimately , the colours add up to black - the absence of all light .
CMY Model
When white light or artificial light hits an object , certain wavelengths are absorbed while others are reflected . The reflected wavelengths are what we see and understand as the colour of the object . Theoretically , we are starting out with all light ( white light ) and are ending up with less light ( the reflected light ). A pigmented surface will absorb every wavelength of light except the one that it reflects ( ex . yellow pigment absorbs all light but yellow ). When you mix different colours together , you are adding to the amount of light that is absorbed - ie , subtracting the amount of light that is reflected . This is why it is considered subtractive .
RYB Model
M + Y = R C + Y = G C + M = B C + M + Y = K
When subtractive primaries are mixed , more light is absorbed than reflected , making secondary colours ( red , green , blue OR green , violet , orange ) that are darker and duller than the primaries . Mixing all three subtractive primaries together , makes black .
Y + B = G R + B = V R + Y = O R + Y + B = K
Most printers recognize the CMY model as the standard colour model . And even though it does not produce as wide a range of colours as the CMY model , the RYB model is still considered the basis of the traditional artist wheel and colour theory .