The Autochrome was a process for producing photographic images on glass with natural colors. Louis Lumière patented in 1904 was in essence coating a glass plate with a colored layer which had to equal parts potato starch dyed red, violet and green. This procedure color photography was in effect until 1930, although the final glass stand was replaced by plastic roll.
autochrome (autochrome in French) : a photographic technique patented in 1903 by the brothers Lumière , and marketed from 1907 by several manufacturers. In fact, it was the only color process until 1935, when Kodachrome (the first type of color film diapostiivas marketed on a large scale) became popular. In Spain its use is known by the likes of Santiago Ramon y Cajal, circa 1911
The viewer we have in our collection is Mackenstein , a company founded in 1872 and also performed several patents related to these plates autochrome and other photographic materials and is accompanied by a plate autochrome in which it shows a couple holding hands
the autochrome consisted roughly of coating a glass plate on which previously provided the image in black and white with a mixture colored layer equal parts of potato starches dyed red, violet and green. It should be borne in mind that, to the treated glass influences the display light incident on the slide, which gives a luminosity varied and life. For these reasons, the autochrome plates are unique, because there are no negatives for copies, if not positive plates which are transparent.