by Peter Irwin <pirwin@[EMAIL PROTECTED]
>
Oct 31, 2007 at 02:28 AM
Nicholas O. Lindan <see@[EMAIL PROTECTED]
> wrote:
>
> Sensitometry is usually performed at a color temperature
> of 5,500K - a blue filter and a dim bulb (2,250K (?))
> is the usual source. The bulb is calibrated to a
> 'standard' bulb.
It is 2360K (The same colour temperature as the old
acetylene sensotmetric lamps) screened by a liquid
Davis-Gibson filter to convert it to 5400K.
This was the standard adopted at the International
Congress of Photography in Dresden in 1931.
For less exacting purposes you can use a 2850K
sensotometric lamp screened with a Wratten 78AA
filter.
This is book-knowledge - I have no personal
experience with such things.
Peter.
--
pirwin@[EMAIL PROTECTED]
