Quote:
Originally Posted by Roger Hicks  Dear Dan, True. You said 'balanced for tungsten' (post 1)
which is equally meaningless -Cheers, Roger |
Balanced as with color films are balanced for indoor
or outdoor use; ie taken to mean tungsten or daylight.
Unless I've forgotten the terminology?
Apart from all that I'm now struggling to understand
why precisely filter factors are necessary. Any clues?
I think it may have to do with an averaging of negative
densities across the spectrum. Filtering out some portion
of the spectrum does not affect film sensitivity yet most
filters require an increase in exposure. Dan