U of S | Mailing List Archive | alt-photo-process-l | RE: Gum tonal range (was Miracle size for gum)

RE: Gum tonal range (was Miracle size for gum)

Marek wrote:

Actually your point is well taken and it is not how many steps on the stouffer wedge can be printed, but how many separate grey tones from black to white can be distunguished in the print. To me a good test for that is printing the step wedge, but any low density, or even curved test negative will do.

To this extent there is 12 separate steps in this test print, and you will notice how delicate the highlights are, gradually disappearining into the white of the paper. Very much like palladium print. You would use a palladium like negative to print that as well if you will look at the DR.
Very nice. Your step tablet exhibits quite "law-like" behavior, for gum, although the highlights -- steps 10 and above -- are not as smooth as with what I called the "more literal" processes. One comment: Generally, with a step wedge, one would like to use enough exposure so that one had several steps of indistinguishable black as well as several (or many) steps of indistinguishable white.

For comparison, for pure Pt (not Pd or Pt/Pd), I generally use negatives with a DR of at least 2.1 (14 steps) up to as much as 3.0 (20 steps).

Best regards,