Technical Pan Developers
2003-08-23 by Paul Roark
I have been comparing the Kodak Technidol developer with the Photographers'
Formulary TD-3 developer.
They are both winners. For different purposes or "looks," each is best.
They are convenient liquids with, potentially, reasonably long lives. The
Kodak liquid packets I tested were more than 2 years old, but appeared to be
producing results right where I expected from past tests. TD-3 is a
2-solution concentrate that I mixed direct from the concentrates with
syringes and scales. (Syringes would be accurate enough.) Photographers'
Formulary told me that the concentrated solution A (developer) can be put in
the refrigerator for a fairly long while (left unspecified). (Solution B is
an alkaline activator that does not need such treatment.)
Both developers produced reasonably even negatives -- no small
accomplishment for Technical Pan ("TP").
They are both very sharp, with a very slight mid-tone sharpness advantage
going to TD-3, and a highlight sharpness advantage to Technidol.
TD-3 is very much a "compensating" developer which, at the recommended 3
minute agitation cycles, causes it to have a strong chemical sharpening
("adjacency effect") in the mid-tones. (TD-3 has a smoother curve and
better highlight contrast with its recommended 3-minute agitation cycle,
when compared to a 1-minute cycle.)
The Technidol produces a straight-line characteristic curve, and I see
little evidence of significant chemical sharpening. (I used a 1-minute
agitation interval with the Technidol. In the past I've seen unevenness
with longer agitation cycles on this faster developer.)
The TD-3's curve is very much an "S" shape. When the highlights are
equalized in contrast to the TP highlights the grain of the TD-3 is
significantly rougher.
TD-3 developer does not appear able to reach a dmax that is very high. It
appears to be a low-contrast developer by nature.
The developing procedures recommended by Photographer's Formulary seem to be
right on. I, essentially, use Kodak's recommended procedures also, with
some agitation modifications.
TD-3 probably has a longer range, or more latitude. The Nikon 8000 was able
to separate the full 13 stops of my test procedure with both developers.
However at the high end, it appeared that Technidol was going flat. So, for
the very rare subjects with dynamic ranges above 12-13 (an extreme range),
TD-3 may have an advantage.
Just below the shoulder, the Technidol scanned better. Since I often like
to expand the contrast in very bright skies, this could be an advantage.
Both have essentially equal speed, with Technidol having more contrast to
minus 4 stops, and TD-3 possibly reaching into that next stop a hair.
(Again, it's the difference between straight-line and "S" shaped curves.)
I'm ending my tests of TP for now. (On to other things.)
Both Technidol and TD-3 are winners in their own ways.
I'm going use TP with Technidol for a while. I like the way its
straight-line curve is scanning. I used to prefer a compensating developer,
chemical sharpening, and the "S" shape characteristic cure. However, that
was pre-Photoshop. I now want to see if the straight-line approach has an
advantage in the highlights.
Thanks to all for the information you have sent on this issue.
Paul
http://www.PaulRoark.com