Sergei Mikhailovich Prokudin-Gorskii was a color photographer before his time, who undertook a photographic survey of the Russian Empire for Tsar Nicholas II. He was able to capture color by taking three pictures of each scene, each with a different red, green or blue color filter. Walter Frankhauser, a photographer contracted by the Library of Congress, manually registered and cleaned up some 120 of the original high-resolution scans, with breathtakingly beautiful results. The results of his effort can be seen at the online-exhibit The Empire That Was Russia.

Using computer-vision technology to automate the registration process, one can now for the first time view almost the entire collection of the Prokudin-Gorskii photographs in color. The color images on these pages were obtained by automatically registering these three pictures to obtain a color image of each scene. The computer program to do this was written in MATLAB by Frank Dellaert using computer-vision technology commonly used in 'mosaicking'. By clicking the links on this page you can view thumbnails of the almost 2000 images purchased by the Library of Congress, and each thumbnail is linked to a larger version of the corresponding color image.

One caveat: the quality of the images is nowhere near the superb photographs on the LOC website. The resolution is fairly low, as all original three-frame glass-plate scans had to be downloaded, and the high-resolution versions were prohibitively large (70 MB per scan). In addition, the warping process introduces some blur, further degrading the sharpness of the images. Finally, there was no attempt to retouch the images to remove the many scanning artifacts, dirt and other damage that was done to the originals, nor did I attempt to restore the color balance to obtain 'nicer' colors.

Frank Dellaert is not affiliated with the Library of Congress. This project is a private venture, not endorsed or funded by Carnegie-Mellon University. The images themselves are not subject to any known restrictions, according to the LOC web-site.