Re: exposure calculation with paper negatives

From: taco <taco_at_domain.name.suppressed>
Date: Thu 18 Mar 2004 - 13:24:51 PST

Jean-Marc Becker wrote:

>But the sensitivity is strongly different, regarding the colour temperature
>of the ambient light. Papers are very sensitive in blue light, far less in
>yellow, quite blind in green, and totally unsensitive in red light.
>
>
>
But Guy Glorieux states in his mail to Earl:

>But the central point that has not been mentionned is that paper emulsion is manufactured to react to yellow light (enlarger bulb) and not blue light (daylight). It will react very differenttly under sunshine and cloudy conditions in terms of BOTH exposure time AND constrast.
>
I, innocent as I am, always shared the opinion of Jean-Marc: Why is
safelight yellow and not blue?
Taco

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Received on Thu Mar 18 13:25:37 2004

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