Re: Pyro density

From: Sandy King (sanking@hubcap.clemson.edu)
Date: Tue Dec 14 1999 - 21:14:22 /etc/localtime


>THIERRY GUICHERD wrote:
>
>> someone can help me to read densities on a film wich is pyro developed
>> with a densitometer?
>> Wich filter or status.
>> thank you.
>
>Ideally, you'd want to use the filter/status that most closely matches the
>spectral sensitivity of your emulsion. Try the either UV setting or the
>BLUE setting. If you don't have either of these settings, try getting
>yourself a violet gelatine filter like a Wratten #32, #33 or #34A, tape it
>in place on the densitometer and then zero the densitometer on it.
>Subsequent measurements will then include this violet bias. This will only
>be a stop-gap method of changing the response of the densitometer, and as
>long you stick with it, it should work for you.
>
>Which brand/model of densitometer do you have?
>
>Dave

There are four settings on my Macbeth TD-504 color densitometer: red,
orange, green and blue. I use the orange filter for reading the silver
density and the blue for silver density plus stain. However, for printing
in silver, especially with VC papers, the blue channel reading may suggest
a density range that is actually inflated. Phil Davis suggests taking a
reading mid-way between the blue filter and green filter reading for silver
printing.

Thanks for the suggestion about the use of a violet gelatin filter. I
presume this would be to calibrate for UV printing?

Sandy King



This archive was generated by hypermail 2b29 : Tue Jan 11 2000 - 12:10:49