Produced using separate screens: one in the camera for taking the negative and a second for viewing the positive print. The screen had the same crisscrossing lattice of red, green and blue squares as Paget Color, but the squares of color were smaller. Like Paget Color, the screen was separate from the plate, not permanently combined with it as with Autochrome.

Separate screens required the position of the viewing screen covering the positive plate to exactly match that of the taking screen covering the negative. Clare Livingstone Finlay patented a process that allowed the screens to be reliably registered using colored marks along their margins (Finlay 1932a).

In a second patent (Finlay 1932b), Finlay addressed the issue of parallax: since the viewing screen was separated from the positive image by the thickness of the glass plate, viewing the image from an angle meant the filters were no longer perfectly aligned. Finlay added an extra step in which a positive image was created on the rear surface of the viewing screen, which eliminated the separation between the screen and the image.

A further issue with screen processes was the loss of light due to the filtering. Two screens allowed the colors in the camera screen to be less saturated than in the viewing screen, which allowed faster shutter speeds than Autochrome (Pénichon 2013, 38–40). Finlay Colour was also able to take advantage of the faster negative plates of the time (Coe 1978, 68).