Land camera

Land Cameras are instant cameras with self-developing film named after their inventor, Edwin Land, who created them while working for Research Row in Boston, Massachusetts. They were manufactured by Polaroid between the years of 1947 and 1983. Though Polaroid continued producing instant cameras after 1983, the name 'Land' was dropped from the camera name since Edwin Land retired in 1982. The first commercially available model was the Polaroid Land Camera Model 95, which produced prints in about 1 minute, and was first sold to the public in November, 1948.

The process, invented by Polaroid founder Edwin Land, was to employ diffusion transfer to move the dyes from the negative to the 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.

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