Pyro or Silver (Part 3 of 3)

FotoDave@aol.com
Sat, 31 Jan 1998 20:36:20 -0500 (EST)

Oh, I need to add one more note about using Arista Premium Halftone Supreme
(APHS) from freestyle for making continous-tone enlarged negatives. I have
used it before for non-critical works. In general the film is made for making
halftone negatives, so you can imagine that the quality control is performed
on whether it can hold the dots, it is densed enough, etc. but not on the
consistency of halftone. Maybe because I have written software for quality
control in the past, that I am particularly interested in consistency. I have
suspected the consistency, but have recently made a formal test.

I put a 35mm Stouffer step tablet into my enlarger and arrange it so that I
could expose 6 of them on the *same* piece of APHS film, then I developed this
single piece in Dektol 1:1 and took the densities. For each step, I took the
density at the center of the step. It is not worth posting the whole thing,
but here is just a sample:

[ Set your printer or screen to fixed-size font to view the table properly.
The densities are multiplied by 100 so that I don't have to type in the
decimal point. ]

step 5: 205 217 212 204 189 177 [range = 40]
step 8: 88 91 86 92 106 101 [range = 20]
step 11: 34 29 26 34 24 22 [range = 12]

As you can see, it is very inconsistent. I don't know about the cost of pyro
developer. If it is expensive, I think it would be better to use a truly
continous-tone negative.

If you have any question or disagreement, I would be happy to hear them. The
later part of this message might be a little unclear because I am caffein
depleted and starting to get some kind of compensating effect. :)

I hope not but I think I will get some flame, but oh well ....

Peace,
Dave
:)