Normally we use color filters of different
Hues for our filters. We don't have to; they only have to be different
wavelengths. At the right two different wavelengths of the Hue Red
have been used to produce a full color image.Using colors that are close in wavelength will produce muddier colors, as they will not have much contrast. The greatest contrast and most vibrant color image will be produced when the filters are from opposite ends of the spectrum. Thus a Red filter for the long record, and a Violet filter for the short record will produce the best results.