Jim Strain wrote:
"For what it is worth, I echo the sentiments of BTZS plus use of
the Phil Davis programmed hand computer. When I use that machine,
available from Darkroom Innovations, for my pt/pd or Palladio negs, they
invariably come out within 1/2 stop of my desired density range."
It sounds good.
But Jim, the main reason I have not used a 'system' before for pt/pd is that
when I started platinum printing I sought out the best platinum prints I could
find in terms of subtlety of gradation or density range. The aim was to
establish a bench mark. This meant looking at work in museums and collections
from the 1880s inwards. To my eye the best in terms of range or gradation were
by far and away those of Frederick Evans. As he used commercial platinum paper
it was clear that his mastery of the process depended not only on the subject
and exposure but also on the development of the plates. I telephoned his son or
nephew who lived in Epsom, to ask what Evans had used for developer. I was told
that he used acid amidol. Coincidentally this was the developer that we had
found on the 'experimental' workshop, that Peter Marshall has mentioned on the
list, that gave the best internegs and in camera negs in conjunction with FP4.
By chance we found that the best commercial developer for large format negs for
pt/pd was Ilford PQ Universal which is a paper developer. We only included it in
the test against the rest because it was on the shelf in the dark room. Of
course Frederick Evans was working well before the zone system and computers.
The results with amidol are so good that I have never seen any reason to change.
The gradation is beautiful. The separation of tones in the highlights and the
shadows is stunning. And the possible tonal range is plenty enough for carbon
let alone pt/pd and salt. Normal development time is comparable with that for
paper. I have seen very very few modern platinum prints that can compare. All
I need to do is expose for the mid point that I choose and develop accordingly
as I know that the pt/pd paper will handle the range. I get the results that I
want.
As nothing could be much simpler, anything that is going to replace this method
is going to have to be bloody good as I get excellent results without a computer
and without the zone system.
I hope that last comment was not provocative and, despite any evidence to the
contrary, I am willing to listen.
Terry