Hello,
I know the folks from the Denver Public Library quite well - very nice people. Colorizing B/W photos is an Art that was quite often done in the old day (e.g. by H.W.Jackson). There's no reason why it shouldn't be done today on a computer. By the way, we - that is the Image and Media Lab of the University of Basel, Switzerland - are collaborating with the DPL to restore old color photographs to the original colors, one of our basic research topics (see link). I was in Denver 2 weeks ago (by Amtrak, going from California to Boston to the annual conference of the moving image archivists, AMIA). As one of the few RGS & DRGW NG buffs in Switzerland, I'm looking forward to some wonderful, restored color pictures of my favorite railroads
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