How should I proceed with photographing or videotaping trains, locos, etc.?
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For a comprehensive account of all that is involved in photographing IR, and suggestions on equipment, etc., please see A railfan's guide to photography on the Indian Railways by S Shankar.
IR is skittish about anybody photographing or videotaping anything at supposedly strategic locations such as railway stations, bridges, workshops, etc. Technically,...
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a permit is required for almost all photography or videotaping done on or near railway premises.
However, in practice, this rule is often used by the railway security persons (RPF, GRP, etc.) just as an opportunity to extract bribes. More often, a security person might just be operating under an antediluvian notion of "security" and harass photographers with or without permits. Other railway staff (drivers, station masters) are sometimes quite sympathetic to railfans while others (shed foremen, particularly) might insist on following the rules and seeing a permit.
Lineside photography in general does not require a permit (unless near a bridge, tunnel, etc.), but security personnel may sometimes be ignorant of this. One will often find security personnel and railway staff both more friendly and accommodating at the smaller stations.
Many railfans have had good results without an official permit by being discreet and using small cameras (compact point-and-shoot cameras) which can be concealed easily. Bulkier and complex equipment (such as sophisticated SLRs, long zoom lenses, tripods, or video recorders) is more likely to be noticed and may result in questioning or trouble, especially if the photographer does not have a permit. Similarly, flashes may draw more attention, so unless it is essential, it is probably better to avoid them. The best advice is to avoid overdoing it and not to draw too much attention to oneself.
Some hints
Avoid the platforms or areas near the RPF or GRP post where the security personnel tend to be. Overbridges often provide good vantage points of tracks and shunting yards. An empty train stabled on one track can sometimes provide the best views of action on adjacent tracks, provided one can get into it (and remember to get out of it before it is shunted away...).
The end of a platform is a good place to get shots of a train pulling in or out of a station, without the crowds that are present near the middle of the platform. If you have a good SLR with a fast lens, ISO 100 film is the best as you can make good enlargements of the interesting portions of prints. With a compact point-and-shoot camera, or for candid pictures and action shots, it may be better to use ISO 200 or 400 film, which is also more versatile in different light conditions.
Although Station Masters and other officials at railway stations are not technically empowered to give you permission to take photographs, if you do not have a permit, it is sometimes a good idea to talk to the Station Master or other official and make sure that they understand you only intend to take a few hobby photographs. This will help avoid awkward confrontations with police or other security officials.
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Source: IRFCA