With the SPORRS list members and railfans in general worrying about accurate color rendition and sharpness of photos of their favorite diesels, I was really shocked to see that Greg was curious about the use of infrared film for shooting trains!
IR film was invented in order to identify wartime camouflage by recording the IR light reflected by tree leaves, subjects which are "bright" in IR light. By providing a "false color" on the film for the chlorophyl in leaves, the leaves photographed as one shade while the camouflage photographed as another shade. With b&w IR film, the real leaves were rendered as white, while with color IR film the leaves were rendered as bright red. Both of these results depend on which type of IR film and types of filtration selected by the photographer. There are many combinations of lens and light filters for different effects on color IR film with different types of subjects. Some of these filters are opaque to visible light, and they even used to make IR flashbulbs! IR film is valuable in forensic sciences. B&W IR film requires a #25 deep red filter when shooting, is extremely contrasty and very grainy. Additionally, IR film requires strict attention to its storage, total darkness camera loading/unloading, preservation of the latent image, and processing. The film's resulting b&w prints with white leaves and black skies (on blue-sky days) are spectacular, but the resulting railroad photos are nothing that I would want to see reproduced in Trains magazine! In college 25-30 years ago I used b&w IR film to photograph old barns and trees, but my favorite was to photograph the otherwise unseen network of veins and arteries underneath the skin of nude female models for a very unusual effect. Not beautiful, but striking. Color IR film comes in slide format, needs the same special handling as mentioned above, and requires yellow filtration to prevent excess blue from dominating the emulsion. IR film converts an IR image into a false-color one, and combines it with regular visible-light components. Because of this, color IR film was used extensively in the medical field to better see arterial occlusions, carcinomas, light reflection and emission by gross specimens, etc. To prevent its camouflage from being detected by color IR films, the modern military produces its camo cloth materials with dyes that are "bright" in IR light, just like real tree leaves, so that today's camouflage materials also photograph as red on color IR films. I have used the color IR film a few times back in college, but never for a train. Just for fun, I always wanted to photograph that camouflage UP diesel with IR film, but I never got out West to try it out! Some IR films are sensitive to heat radiation, depending on their nm rating (nanometer), but I do not remember very much about using this technique. Today's IR video cameras and recorders have made the job of photographing in the dark a snap compared with my experiments of photographing a hot iron in total darkness. Again, this type of IR photography is possible, but for what hobby purpose is beyond me, other than for the fun of experimentation. I would think that the false-color rendition of normal subjects by IR films would be a little too weird for most serious railfans to consider using it to shoot some trains. But if anyone wants to spend their time and money doing this as a test, I am sure the rest of us would want to see your results. John B. Corns _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866] -> SPORRS: 'Serious Photographers Of Railroad Related Subjects' -> Web Site: http://www.anet-stl.com/acphotog/sporrs/ -> Message © 1998 SPORRS® - All Rights Reserved
