This is the effect of Mie-scattering. In „normal“ black and white films the whole spectrum of white light is absorbed by the silver grain. The more silver of this kind is in one area of the film, the less light comes trough it; it´s darker than other sections of the film! My film was forgotten for nealy 25 years. The silver grain has been broken while this long time. The very little fragments of this grain correspond in there measurements to the wavelenght of one color in white spectrum of light. For example: 700 nanometer = red light. When white light hits this film; the dwarfen grain fragments of silver absorb only the shorter waves of the white light; green and blue, with 600 and 500 Nm. To the red waves of light the surface of the fragments have the effect of mirrors and reflects this waves as long as they comes out of the film; as red light. This work is highly artificial by this effect, my first aim was only to test the old film. It works by a real special way.