To anyone with knowledge of tri-pack colour films. I am a photographer researching into early tri-pack colour processes, mainly negative-positive processs, such as Gevacolor, Pakolor and others. "How did Eastman Kodak process the second type of Kodacolor film, which was marketed between 1944-49?" The film had a black and white blue sensitive emulsion layer between the yellow filter layer and the green sensitive (magenta dye forming) layer. My theory is: The film was processed in C-22 chemicals to form dye images in the three dye forming layers. Then the film was exposed to white light, through the base, printing the cyan dye layer and the magenta dye layer onto the blue sensitive B/W layer. The film was then processed again in a soft working B/W developer (possibly D-165) to form a weak positive mask image. When the Kodacolor negative was printed onto Kodacolor Paper through the base of the film, the mask would have held back some of the light in the shadow areas of the negative thus lowering the contrast.