Adam Kimball (akimball@finebrand.com)
Mon, 05 Jul 1999 23:17:25 -0700
Sandy,
To be honest, that post was probably a bit confusing. I get a little
frustrated with the terminology I have at grasp. Say if I were to do a N+
development that was to be printed in silver gelatin, I would have a massively
different development time than I would for a N+ to be printed in salted
paper! I'd guess the N+ for salt might easily be twice the development time as
for the N+ for silver gelatin. Correct? So, this N+ stuff is relative to a
process - and, it seems, talking about N+ without specifying some ideal delta
log h is more confusing than it is helpful. So, Sandy, your qualification of a
delta log H is absolutely crucial - just quite a bit lower than what I'd have
ideally for the process at hand.
So, what I was getting at is that I need a long negative (delta log h of 2.0 or
so) from a subject that only contains a stop or so of contrast! A N+2
development (speaking in terms of cyano, now) would only get me to three stops
in the negative - not enough for my needs (rather, desires ;)
I think our times check out within a small margin. My 14 minute development is
definately around N+2 or N+2.5 at the most. However, I'd like to get N+3 at
least, or N+4 ideally.
Does that make more sense?
-Adam
Sandy King wrote:
> Adam,
>
> Perhaps I don't understand your terminology. If I do, however, there
> appears to be something wrong with your Rollo Pyro. My tests with Pyro ABC+
> (same as Rollo Pyro) and Ilford FP4+, processed at 74F in a tube with
> constant (but gentle) agitation (3 oz per sheet of 5X7 film), give the
> following results, assuming density range of 1.5.
>
> N -2 4.5 minutes
> N -1 5.45 minutes
> N 7.5 minutes
> N +1 9 minutes
> N +2 12.5 minutes
>
> Times for HP5+ are slightly longer to the same CI.
>
> Sandy King
>
> >Hi all,
> >
> >I have no idea why, but since I began alt stuff a number of years ago,
> >I've compulsively taken pictures of subjects that have a stop, or two of
> >contrast. Every so often, I'll meter a scene and be amazed to read
> >three or even four (!) stops of contrast - but this is all too rare for
> >me. Maybe, I'll simply have to start making silver gelatin prints
> >again... maybe someone who has spent time with this problem can give me
> >a pointer or two..
> >
> >I'm having my best luck right now with FP4+ developed in Rollo Pyro in a
> >Jobo. Yesterday, I processed a few negs (the original scenes all had >2
> >full stops contrast) for a whopping 14 minutes at 22C. They are just at
> >the edge of being useful to me now.. I'll give a go up to 16 or 17
> >minutes next round, but expect to see overall fogging setting in soon.
> >
> >Increasing the stain might be another avenue. Maybe PMK used in the
> >Jobo might yield more stain? Any thoughts on that? Most of the
> >subjects I shoot stay around for years, so I'd rather reshoot than do a
> >pyro redevelopment or make copies (dust, pinholes, newton's rings,
> >etc...)
> >
> >Any ideas for that elusive N+++ or N++++?
> >
> >-Adam
This archive was generated by hypermail 2.0b3 on Thu Oct 28 1999 - 21:40:35