Most of the photos on this site were extracted from reference images (high-resolution tiffs, 20 to 200 megabytes in size) from the Library of Congress research archive. (To query the database click here.) Many were digitized by LOC contractors using a Sinar studio back. They are adjusted by your webmaster for contrast and color in Photoshop before being downsized and turned into the jpegs you see here.

January 1943. "Indiana Harbor Belt R.R. switchman demonstrating signal with a fusee, used at twilight and dawn when visibility is poor. This signal means stop." Calumet City, Ill. 4x5 Kodachrome transparency by Jack Delano. View full size.
Read more about fusees or railroad flares. The article uses the very same picture as an illustration, although much bigger (5275x6999 i.s.o. 1200x1323 pixels), you may see what improvement Shorpy's editing effort brings to us!
I would like to show this to all the Flickr fanbois who think they invented this technique with digital cameras and laser pointers.
Just goes to show that with something as old as photography, it's not easy to come up with new ideas. Digital has not brought much to the table creatively but because of it's supreme convenience has resulted in lots more photos being taken.
Lets hope some of them are still around in 100 years.
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