Foresighting Color Photography
In an remarkable effort the russian photographer Prokudin-Gorskii build a camera that was able to capture three black and white images on glass plate negatives, using red, green and blue filters. He then presented these images in color in slide lectures using a light-projection system [right] involving the same three filters.
The images are now being digitalized by the library of congress for the exhibition "The empire that was Russia". For the digital process, the original tri-part glass negative is scanned with an overhead digital camera in grayscale mode. Image-editing software converts the scan of the entire plate from negative to positive form. The entire plate is then reduced to 8-bit grayscale mode. Under magnification, the quality of each image on the plate is reviewed for contrast, degree of color separation, extent of damage to the emulsion, and any other details that might affect the final color composite.
The resulting images look amazing...
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