[pure-silver] Re: Adding Pot Bromife to PC-TEA
- From: "Koch, Gerald" <gkoch02@xxxxxxxxxx>
- To: "'pure-silver@xxxxxxxxxxxxx'" <pure-silver@xxxxxxxxxxxxx>
- Date: Fri, 7 Jan 2005 15:51:38 -0500
I had poor results with Gainer's original formula which I list below for
discussion purposes.
Pat Gainer's Original PC-TEA Developer
TEA ................ 100 ml
Ascorbic acid ...... 9 g
Phenidone .......... 0.25 g
The negatives had an unexceptable level of developer fog and lacked contrast
even though the density was fine. Attempting to get more contrast caused the
density to become too high.
A few weeks ago Gainer changed the formula in an APUG post by reducing the
amount of Phenidone to 0.225 g. This helped a bit with the contrast/density
problem. Soon after that someone suggested adding 0.25 g of potassium bromide
to the concentrate. This really cleaned up the negatives and greatly improved
the contrast/density problem.
I still was not completely satisfied and decided to cool the action by reducing
the amount of TEA and by substituting Dimezone-S for the Phenidone. I think the
Gainer formula has too much Phenidone in relation to the amount of ascorbic
acid.
The formula that I am testing now is
TEA ................ 50 ml
Propylene glycol ... 50 ml
Ascorbic acid ...... 9.0 g
Dimezone-S ......... 0.25 g
Potassium bromide .. 0.25 g
The fog problem is gone and tonal separation is what one would wish from a good
developer. Development time was a bit longer 8 minutes instead of 7-1/2. I am
very happy with results so far but will continue testing with other films.
The TEA has some solvent action on silver halide and therefore produces finer
grain than using some other accelerant such as metaborate.
Jerry
-----Original Message-----
From: pure-silver-bounce@xxxxxxxxxxxxx [mailto:pure-silver-bounce@xxxxxxxxxxxxx]
On Behalf Of Gene Johnson
Sent: Friday, January 07, 2005 2:09 PM
To: pure-silver@xxxxxxxxxxxxx
Subject: [pure-silver] Re: Adding Pot Bromife to PC-TEA
I think what I really wanted to ask is if it reauired a change in developing
times, and if you've seen any change in characteristics. I'm currently still
using my PC-Kbr-Prestone stock and adding borax and sodium carbonate to make
working developer. Like it just fine, wondering if I should try to go to the
single step concentrate when it's gone :)
----- Original Message -----
From: "Koch, Gerald" <gkoch02@xxxxxxxxxx>
To: <pure-silver@xxxxxxxxxxxxx>
Sent: Friday, January 07, 2005 10:50 AM
Subject: [pure-silver] Re: Adding Pot Bromife to PC-TEA
> I haven't had a chance yet to measure it.
>
> -----Original Message-----
> From: pure-silver-bounce@xxxxxxxxxxxxx
[mailto:pure-silver-bounce@xxxxxxxxxxxxx]
> On Behalf Of Gene Johnson
> Sent: Friday, January 07, 2005 12:53 PM
> To: pure-silver@xxxxxxxxxxxxx
> Subject: [pure-silver] Re: Adding Pot Bromife to PC-TEA
>
>
> And you're now using 50/50?. How big of a ph change did that cause?
>
>
> ----- Original Message -----
> From: "Koch, Gerald" <gkoch02@xxxxxxxxxx>
> To: <pure-silver@xxxxxxxxxxxxx>
> Sent: Friday, January 07, 2005 8:59 AM
> Subject: [pure-silver] Re: Adding Pot Bromife to PC-TEA
>
>
> > One of the reasons I started using a mixture of TEA and propylene
> > glycol
> for the
> > developer is that it allows me to control the amount of TEA and
> > hence the
> pH of
> > the working solution and still have a waterless concentrate. One
> > can
> achieve a
> > lower pH than for Gainer's formula by adjusting the ratio of glycol
> > to
> TEA.
> >
> > Many years ago there was a product (can't remember the name) to stop
> prints from
> > curling. You soaked the washed prints in a bath made by diluting
> > this
> stuff and
> > then dried them. The product was based on one of the glycols.
> >
> > There is an OTC treatment for "swimmer's ear" which is 2% acetic
> > acid in glycerin. Works great to getting earwax out.
> >
> > -----Original Message-----
> > From: pure-silver-bounce@xxxxxxxxxxxxx
> [mailto:pure-silver-bounce@xxxxxxxxxxxxx]
> > On Behalf Of John Black
> > Sent: Friday, January 07, 2005 11:31 AM
> > To: pure-silver@xxxxxxxxxxxxx
> > Subject: [pure-silver] Re: Adding Pot Bromife to PC-TEA
> >
> >
> >
> >
> >
> > > I never measured the temperature. I will do that when I make
> > > another
> > batch
> > > (which may be awhile). I think Gainer stated in either his
> > > article in PhotoTechniques or in a post on the net that the
> > > ascorbic acid would
> > eventually
> > > go into solution without heating after a few days.
> > >
> >
> > I will try this and see how little heat is necessary for solubility
> > of the ascorbic acid. I would prefer one of the more fluid glycols
> > over methanol
> but
> > want to avoid the excess heat. I will let you know about the temp.
> >
> > BTW, since glycerol can be used (although in larger concentration)
> > to
> prevent
> > curling in paper, I wonder if either of the glycols might have a
> > good
> effect on
> > curling of paper of film? On second thought, the washing surely
> > removes
> it so
> > it probably doesn't.
> >
> > OT, propylene glycol is a great cerumenolytic (dissolves earwax) and
> > can
> be used
> > to good effect in cleaning out obstructed ears. Perhaps a good use
> > for
> outdated
> > HC110?
> >
> > JB
> >
> >
> >
> >
> >
>
============================================================================
> ====
> > =============================
> > To unsubscribe from this list, go to www.freelists.org and logon to
> > your
> account
> > (the same e-mail address and password you set-up when you
> > subscribed,) and unsubscribe from there.
> >
>
============================================================================
> =================================
> > To unsubscribe from this list, go to www.freelists.org and logon to
> > your
> account (the same e-mail address and password you set-up when you
> subscribed,) and unsubscribe from there.
> >
>
>
>
============================================================================
====
> =============================
> To unsubscribe from this list, go to www.freelists.org and logon to
> your
account
> (the same e-mail address and password you set-up when you subscribed,)
> and unsubscribe from there.
>
============================================================================
=================================
> To unsubscribe from this list, go to www.freelists.org and logon to
> your
account (the same e-mail address and password you set-up when you
subscribed,) and unsubscribe from there.
>
================================================================================
=============================
To unsubscribe from this list, go to www.freelists.org and logon to your account
(the same e-mail address and password you set-up when you subscribed,) and
unsubscribe from there.
=============================================================================================================
To unsubscribe from this list, go to www.freelists.org and logon to your
account (the same e-mail address and password you set-up when you subscribed,)
and unsubscribe from there.
Other related posts:
