Instant Photography

Instant photography was born 67 years ago and has ever since remained one of the few milestones of photography that still attracts customers to the day.  Even though technology has advanced a great deal, instant cameras still function with the same chemical reactions that were used in the first instant camera developed in 1947. In an instant camera, a colour film is enclosed in a light tight part of the camera. This plastic film consists of three light sensitive layers, sensitive to the colours blue, green and red. In between each of these layers there is a dye developer, which will later turn the photons into metallic silver. Two more very important layers, the light-sensitive layer and the image layer, are located just above the different light sensitive and dye layers. If you take a picture with an instant camera, light hits the light-sensitive layer (covered in silver particles) of the colour film and causes a chemical reaction. A reagent, a mix of opacifiers (light blockers), alkali and white pigment, then starts off the developing process of the picture. While the picture is being passed out of the camera the reagent is spread over the topmost layer, the light sensitive layer. The different chemicals in the reagent slowly make their way downwards through the different layers (light sensitive layers as well as dye layers). In the light sensitive layers, the photons are turned into metallic silver particles by the reagent. After all of the developer dye has been dissolved, the silver particles can move up to the image layer now that the colours are all fully developed. Which of the colours are developed depends on which of the three light sensitive layers has remained unexposed. At this point, the picture is fully developed but it cannot yet be seen. This last step, the reaction of the acid layer with the opacifiers, results in the opacifiers clearing up. Now, after only a couple of minutes, the picture can be discerned.