In article <542446679wnr@boldyrev.demon.co.uk>, oleg@boldyrev.demon.co.uk says...
>I've ran across a statement which said to lower the ISO of film, when
>shooting indoors, apparently this is caused by a warmer lighting,
>lots of red, which standard emulsions are not exactly suited for. I'm
>shooting HP5+ at 400 and 800 in my own canisters, so what would you
>recommend as a real speed?
Testing under your own conditions will give you the best answer to
the question of what speeds to rate film at under different conditions.
Modern films have fairly even color response, but the meters don't, and
if the metered light is very orange, compensation may be required. BTW,
even flash TTL exposure may vary from the expected - I learned the hard
way on a job with a new Nikon SB-24 and 8008 that they underexposed
TTL flash one stop with B & W film... (I ALWAYS test, now...!)
Hope This Helps