Editing Land Camera (section)

==Film==
[[Image:Polaroid SX-70.jpg|left|thumb|upright|A Polaroid SX-70 camera, manufactured between 1972 and 1981]]
The photography developing process, invented by Polaroid founder [[Edwin Land]], employs diffusion transfer to move the dyes from the [[negative (photography)|negative]] to the [[positive (photography)|positive]] via a [[reagent]]. A negative sheet was exposed inside the camera, then lined up with a positive sheet and squeezed through a set of rollers which spread a reagent between the two layers, creating a developing film "sandwich". The negative developed quickly, after which some of the unexposed [[silver halide]] grains (and the latent image it contained) were solubilized by the reagent and transferred by diffusion from the negative to the positive. After a minute, the back of the camera was opened and the negative peeled away to reveal the print.

In 1963, Land introduced ''Polacolor'' pack film, which made instant color photographs possible. This process involved pulling two tabs from the camera, the second which pulled the film sandwich through the rollers to develop out of the camera. The instant color process is much more complex, involving a negative which contains three layers of emulsion sensitive to [[blue]], [[green]], and [[red]]. Underneath each layer are dye developing molecules in their complementary colors of [[yellow]], [[magenta]], and [[cyan]]. When light strikes an emulsion layer, it blocks the complementary dye below it. For instance, when blue strikes the blue sensitive emulsion layer, it blocks the yellow dye, but allows the magenta and cyan dyes to transfer to the positive, which combine to create blue. When green and red (yellow) strikes their respective layers, it blocks the complementary dyes of magenta and cyan below them, allowing only yellow dye to transfer to the positive.

In 1972, integral film was introduced which did not require the user to time the development or peel apart the negative from the positive. This process was similar to Polacolor film with added timing and receiving layers. The film itself integrates all the layers to expose, develop, and fix the photo into a plastic envelope commonly associated with a Polaroid photo. The [[Polaroid SX-70]] was the first camera to use this film.

Improvements in SX-70 film led to the higher speed 600 series film, then to different formats such as 500 series (captiva), and spectra.