From: epona (acolyta@napc.com)
Date: 07/17/02-06:58:27 AM Z
This is interesting. I tried shooting HP-5 a couple of times back in the day but
ended up staying away from it because I always thought it was a little flat and
lacked a little, how do you say, hutspah? (sp?) Now I know why. Maybe I'll give
it another shot with pyro.
Cheers,
Christine
Clay Harmon wrote:
> Shannon:
>
> Hp-5 is notorious for reaching so-called 'gamma infinity' quickly. That is
> where at some point, additional development does not increase the contrast,
> but only adds additional base+fog density (not desirable!) . You may need to
> use a staining developer such as PMK, rollo pyro or Pyrocat-HD, which will
> give a proportional (to silver density) UV blocking stain in the highlights
> and behaves like additional density when printing UV sensitive processes.
>
> I use HP-5 with pyrocat-HD all the time in my big cameras and it works fine
> with a density range of about 1.3-1.4. The stain actually makes the
> effective density range more like 1.8-1.9. Pyrocat times for the density
> range you're looking for would be about 11-13 minutes at 75 degrees. Check
> out the Sandy King article at www.unblinkingeye.com for all the info. It
> also is one of the cheapest developers around, and is pretty easy to mix.
>
> Staining developers are about the only way to go with HP-5 for alt-photo
> density ranges, unless you only shoot really high contrast scenes. The
> pinhole may be making your efforts a little harder also because of internal
> flare.
>
> Clay
>
> on 7/17/02 12:48 AM, Shannon Stoney at shannonstoney@earthlink.net wrote:
>
> > I am shooting HP5+ in the 8x10 format in a pinhole camera for cyanotypes. I
> > am having trouble getting the highlights dense enough. I am up to a 20
> > minute development time now, and still the highlights only have a density of
> > 1.71. I would like a density range of about 1.6, starting at 0.35, say, in
> > the shadows. (I have to shoot it at like 3200 to get the shadows this
> > thin!) Should I keep increasing the development times? Is it "bad" to go
> > over 20 minutes? I process in straight D-76 in a homemade BTZS-style tube,
> > at 68 degrees. I am thinking maybe I should make the temperature warmer
> > rather than making the times longer. But, then what will I do if I ever
> > have to increase the development time further for a low-constrast scene?
> > (Excuse the cross posting if you read
> > the pinhole and alt-process lists.)
> >
> > --shannon
> >
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ "The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead; his eyes are closed." -Albert Einstein
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