30 Jan
1999
30 Jan
'99
11:30 a.m.
On Jan 30, 19:33, Tony Duell wrote:
Or have it splattered with salt spray :-)
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
The names comes from the fact that if the film was
perfect there's a
reciprocal relationship between the exposure time and the aperture area
Exactly.
In other words, bracket the exposures - take the same
picture at several
different exposures and use the best one.
> The effect is that colour balance can be wildly
different at very
short > > or very long exposure times.
While undoubtedly true in theory, I don't think
this will affect most
people on this group. I've taken a lot of pictures inside buildings
without flash (exposures of 20 seconds, perhaps), using Kodachrome.
Kodachrome is more tolerant than many films, but in general you'd need
exposures over a minute or so to see a serious cast develop.
> Also, ordinary B/W film is
"panchromatic" -- sensitive to most of the
> visible colour range (and also to UV, which is why most professionals
tend
to put a UV or
"skylight" filter on every lens as a matter of course).
That, and a new filter is cheaper than a new lens if you happen to knock
it against something ;-)