510 Pyro notes

Just sharing this in case anyone's interested.

Mixing was longer and more difficult than I expected, perhaps, due to 2
factors. 1: My phenidone was from a 1gm/50ml stock in denatured alcohol. It
took a good while to drive off the smell. 2: the pyro was a little chunky. I
spent a good deal of time crushing the chunks in the hot tea before they
dissolved.
The solution seemed to contain millions of small particles in suspension
(or bubbles), I gave up trying to stir until these went away, fortunately
they vanished as the solution cooled.

I guestimated a 1:100 dilution would take 11min @68F for HP5+/EI400.
Results look a little thin, but I understand this is the 'look' of pyro
negs. I primarily use a diffusion head on my enlarger, and I like dense negs
in general. Will know better after a few test prints.

-Lew

In article ,
"lew" wrote:

Just sharing this in case anyone's interested.

Mixing was longer and more difficult than I expected, perhaps, due to 2
factors. 1: My phenidone was from a 1gm/50ml stock in denatured alcohol. It
took a good while to drive off the smell. 2: the pyro was a little chunky. I
spent a good deal of time crushing the chunks in the hot tea before they
dissolved.
The solution seemed to contain millions of small particles in suspension
(or bubbles), I gave up trying to stir until these went away, fortunately
they vanished as the solution cooled.

I guestimated a 1:100 dilution would take 11min @68F for HP5+/EI400.
Results look a little thin, but I understand this is the 'look' of pyro
negs. I primarily use a diffusion head on my enlarger, and I like dense negs
in general. Will know better after a few test prints.

-Lew

My pmk negatives never look thin, unless there was a screw up.

--
LF Website @ http://members.verizon.net/~gregoryblank

"To announce that there must be no criticism of the President,
or that we are to stand by the President, right or wrong,
is not only unpatriotic and servile, but is morally treasonable
to the American public."--Theodore Roosevelt, May 7, 1918

Well, they are certainly thinner that the pmk I've done, too. But then
again, I didn't use an 'after bath,' as I have with pmk ( but won't in the
future as per recent threads in this forum).
"Gregory Blank" wrote in message
...
In article ,
"lew" wrote:

Just sharing this in case anyone's interested.

Mixing was longer and more difficult than I expected, perhaps, due to
2
factors. 1: My phenidone was from a 1gm/50ml stock in denatured alcohol.
It
took a good while to drive off the smell. 2: the pyro was a little
chunky. I
spent a good deal of time crushing the chunks in the hot tea before they
dissolved.
The solution seemed to contain millions of small particles in
suspension
(or bubbles), I gave up trying to stir until these went away, fortunately
they vanished as the solution cooled.

I guestimated a 1:100 dilution would take 11min @68F for HP5+/EI400.
Results look a little thin, but I understand this is the 'look' of pyro
negs. I primarily use a diffusion head on my enlarger, and I like dense
negs
in general. Will know better after a few test prints.

-Lew

My pmk negatives never look thin, unless there was a screw up.

--
LF Website @ http://members.verizon.net/~gregoryblank

"To announce that there must be no criticism of the President,
or that we are to stand by the President, right or wrong,
is not only unpatriotic and servile, but is morally treasonable
to the American public."--Theodore Roosevelt, May 7, 1918

I've had quite dense negatives with HP5+ and 510. At 1:100 and 6.5
minutes, I'm getting a normal looking curve and printing on 2 1/2
filters. I believe this is the ballpark area that Jay ended up at.
I've only used it a few times and keep getting pulled into other
projects but I'll post things that I run into over time. I think Jay
was using constant agitation and getting 6 minute sorts of times. I
was using 30 second agitations and shooting at 320, incident. The
differences in our times, etc make me wonder if something isn't amiss?
My negatives don't have an extreme stain and I use TF-4 for fixing any
of my pyro or catechol developed stuff. I'll plot some controlled
tests and assign some more meaningful data to this as so far, I've
only done a few things that weren't real important to just get a
general feel for the 510. Maybe Jay can chime in and we can get some
info direct from the source!

On Mon, 31 Oct 2005 10:52:40 -0500, "lew" wrote:

Just sharing this in case anyone's interested.

Mixing was longer and more difficult than I expected, perhaps, due to 2
factors. 1: My phenidone was from a 1gm/50ml stock in denatured alcohol. It
took a good while to drive off the smell. 2: the pyro was a little chunky. I
spent a good deal of time crushing the chunks in the hot tea before they
dissolved.
The solution seemed to contain millions of small particles in suspension
(or bubbles), I gave up trying to stir until these went away, fortunately
they vanished as the solution cooled.

I guestimated a 1:100 dilution would take 11min @68F for HP5+/EI400.
Results look a little thin, but I understand this is the 'look' of pyro
negs. I primarily use a diffusion head on my enlarger, and I like dense negs
in general. Will know better after a few test prints.

-Lew


Craig Schroeder
craig nospam craigschroeder com

I use t4 also, are you printing with a condenser or diffuser head? Do you
think there may be an issue re the purity of the chemicals used? Are there
any different formulations of tea around? Your 6.5/hp5 is pretty close to
published results for fp4 ( which were the basis of my 11m estimate for
hp5/diffuser head).
-Lew
"Craig Schroeder" wrote in message
...
I've had quite dense negatives with HP5+ and 510. At 1:100 and 6.5
minutes, I'm getting a normal looking curve and printing on 2 1/2
filters. I believe this is the ballpark area that Jay ended up at.
I've only used it a few times and keep getting pulled into other
projects but I'll post things that I run into over time. I think Jay
was using constant agitation and getting 6 minute sorts of times. I
was using 30 second agitations and shooting at 320, incident. The
differences in our times, etc make me wonder if something isn't amiss?
My negatives don't have an extreme stain and I use TF-4 for fixing any
of my pyro or catechol developed stuff. I'll plot some controlled
tests and assign some more meaningful data to this as so far, I've
only done a few things that weren't real important to just get a
general feel for the 510. Maybe Jay can chime in and we can get some
info direct from the source!

On Mon, 31 Oct 2005 10:52:40 -0500, "lew" wrote:

Just sharing this in case anyone's interested.

Mixing was longer and more difficult than I expected, perhaps, due to
2
factors. 1: My phenidone was from a 1gm/50ml stock in denatured alcohol.
It
took a good while to drive off the smell. 2: the pyro was a little chunky.
I
spent a good deal of time crushing the chunks in the hot tea before they
dissolved.
The solution seemed to contain millions of small particles in
suspension
(or bubbles), I gave up trying to stir until these went away, fortunately
they vanished as the solution cooled.

I guestimated a 1:100 dilution would take 11min @68F for HP5+/EI400.
Results look a little thin, but I understand this is the 'look' of pyro
negs. I primarily use a diffusion head on my enlarger, and I like dense
negs
in general. Will know better after a few test prints.

-Lew


Craig Schroeder
craig nospam craigschroeder com

Hi Lew and Craig.

The first question I have is; are you printing on VC paper, or graded
paper? A pyro neg that prints with normal contrast on G2 paper will
require VC filtration to G5. If you're printing on VC paper, your
stained negs should look at least as dense as your unstained negs to
print without filtration, and those negs will also print well on Azo
G2, and they'll be far too contrasty for grade 2 enlarging paper.

510-Pyro gives full film speed, or better, so if you normally derate
your film by one stop to ensure good shadow detail, you'll probably
overexpose for development in 510-Pyro, which leads to dense shadows
and flat negs with normal development. I recommend that you begin your
testing by rating your film at box speed, and finding normal
development time for that speed. You might still find that your shadows
are too dense, resulting in flat negs. If so, try increasing your EI by
1/3 stop until you get good blacks in your prints.

I standardize my development at 70F. Pyro developers harden the
emulsion of the film, making higher temps practical, and safe.

If you substituted your alcohol/phenidone solution for part of the
total volume of TEA, that represents a 12.5% reduction in TEA, which
will reduce the pH of your working solution, and might well require
extended development times. Chunky pyro suggests the presence of
humidity, which could oxidise the pyro, and degrade the potency of
your developer. Was the pyro white and fluffy, apart from the chunks,
or was it brownish?

My times are very much in line with Craig's, and my BTZS curves suggest
that 11 ½ minutes @70F with continuous agitation, should give a CI of
about .76 with VC paper, and about .92 with graded paper.

Lew,

don't fret over this. Even if your developer was a total loss, it's
only a few grams of pyro and ascorbic acid, and a few ml of TEA. If
your pyro was degraded, and your alcohol displaced some of the TEA,
your developer might require extended development times compared to a
standard batch, but it will still work. If you don't want to waste your
time finding development times for a developer that you won't make
again, use it 1:20 with 30g/liter of sodium sulfite for a paper
developer, and make a new batch of 510-Pyro without the alcohol, and
with fresh pyro. I hope your negs print better than you expect, and
please let me know if I can be of any help.

Jay

Thanks, Jay:
My pyro is a little off - white, so I'll extend the dev time. What's your
opinion re increasing concentration (eg 1.5:100)? Also, wouldn't the alcohol
have been driven off during heating/mixing? Embarrassingly, I haven't got to
the prints yet.
-Lew
wrote in message
oups.com...
Hi Lew and Craig.

The first question I have is; are you printing on VC paper, or graded
paper? A pyro neg that prints with normal contrast on G2 paper will
require VC filtration to G5. If you're printing on VC paper, your
stained negs should look at least as dense as your unstained negs to
print without filtration, and those negs will also print well on Azo
G2, and they'll be far too contrasty for grade 2 enlarging paper.

510-Pyro gives full film speed, or better, so if you normally derate
your film by one stop to ensure good shadow detail, you'll probably
overexpose for development in 510-Pyro, which leads to dense shadows
and flat negs with normal development. I recommend that you begin your
testing by rating your film at box speed, and finding normal
development time for that speed. You might still find that your shadows
are too dense, resulting in flat negs. If so, try increasing your EI by
1/3 stop until you get good blacks in your prints.

I standardize my development at 70F. Pyro developers harden the
emulsion of the film, making higher temps practical, and safe.

If you substituted your alcohol/phenidone solution for part of the
total volume of TEA, that represents a 12.5% reduction in TEA, which
will reduce the pH of your working solution, and might well require
extended development times. Chunky pyro suggests the presence of
humidity, which could oxidise the pyro, and degrade the potency of
your developer. Was the pyro white and fluffy, apart from the chunks,
or was it brownish?

My times are very much in line with Craig's, and my BTZS curves suggest
that 11 ½ minutes @70F with continuous agitation, should give a CI of
about .76 with VC paper, and about .92 with graded paper.

Lew,

don't fret over this. Even if your developer was a total loss, it's
only a few grams of pyro and ascorbic acid, and a few ml of TEA. If
your pyro was degraded, and your alcohol displaced some of the TEA,
your developer might require extended development times compared to a
standard batch, but it will still work. If you don't want to waste your
time finding development times for a developer that you won't make
again, use it 1:20 with 30g/liter of sodium sulfite for a paper
developer, and make a new batch of 510-Pyro without the alcohol, and
with fresh pyro. I hope your negs print better than you expect, and
please let me know if I can be of any help.

Jay

Also, any chance of bumping up the ph or getting more pyro into the mix?
-Lew

lew wrote:

Also, any chance of bumping up the ph or getting more pyro into the mix?
-Lew




TEA comes in (at least) 2 grades. The commercial grade as produced by
Dow has about 15% diethanolamine which actually increases the pH of a
given % dilution. The grade you will get from The Chemistry Store is 99%
as would be used in cosmetics, etc.

I'm not sure that the heating drives of all the alcohol, even though the
temperature is above the alcohol boiling point. Phenidone can be
dissolved in TEA to form a stock solution, which would eliminate the
question. I am not averse to using 1/4 tsp of phenidone as 1/2 gram. So
far as I know, noone has done a sensitivity analysis to see how critical
the measurements are to this developer. Some years ago I did such an
analysis for D-76 (Petersen's Photographic, April 1973, "Kitchen Tested
Soups" ) that showed that + or - 1/8 tsp of the metol and/or
hydroquinone in a quart of D-76 would have no appreciable effect on
development.

Lew,

I wouldn't worry about trying to adjust your developer at this point.
It is what it is, and will remain so until it's used up, so I recommend
that you simply adjust your development times to suit.

Hi Pat.

It's good to see your posts, as I always learn something from them.
Where would one find the commercial grade of TEA produced by DOW? What
kind of pH increase could one expect by substituting the comercial
grade for the cosmetic grade? Are you enjoying the fall colors? I hope
all is well at your house.

Jay