Filmdensities?

[naaldvoerder]

Hi Apugies,

I,m having trouble with me filmdevelopment. Can anyone of you tell me what densities a negative should have in detailed black and detailed white to be comfortably printed on grade 2-2,5? I do have a gadged to measure densities, so i hope this would aid my development, for instance by taking 3 frames of a gray card 1 two stops over and 1 two stops under on everyexposed film and adjusting development till i get the right densities, (if i knew what they were)

Isa this a sound plan? Any comment appreciated!

JJ

 

[Donald Miller]

Typically the test that one does to determine exposure is to measure at what density exposure breaks the film threshold. That is normally a measurement of .10 above film base plus fog. That would correspond to an exposure four stops less then meter reading. The corresponding highlight density will depend on the enlarger light source. Typically that is quoted as a Zone VIII value. That would be three stops above meter reading for a uniformly light textureless surface. The value for this is typically valued at 1.10-1.15 for condensor enlargers and 1.20-1.25 for diffusion light sources.

This above is all Zone System parlance. There are other systems and tests to determine exposure but the explanation that I gave is more in line with the question that you posed.