Soeren said:Martin
I must disagree on the filmspeed issue. I find ISO 50 - 100 very usefull for urban shots at night, especially ISO 100 slidefilm. there is plenty of light to make everybody happy
A friend of mine uses Pan F at night, He don't like Efke 25 because it's to fast (Reciprocity failure issue)
Astrophotographers like very slow film to catch startrails (the very long exposures you mention).
Cheers Søren
FP4+ (ASA 125) is my preferred night photo film. Estimating (or sometimes completely guessing) exposure time is, to me, much easier when starting off pretty far into reciprocity failure. The longer time also allows me to correct problems during exposure rather than in the darkroom. I can burn/dodge in front of the lens, block the lens if an airplane or car goes by, and run around in the scene to light objects by hand.
The grainy look of faster films doesn't appeal to me for most subjects. If I want faster exposure times, I'll expose at a wider aperture. Normally, I stay between f/8 and f/16.