Article on Pyro Developers

sanking · Oct 10, 2003

john_s said:
Ole says above"Think you could change the recipe to give 1000ml final solution? It would be a lot easier for those of us who put the finished solutions in 1000ml (or 100ml, in my case) bottles. "

That's what I was driving at when I suggested 769g with water to make 1000mL, based on Sandy's figure of 1kg pot carbonate plus 1Litre water to make "approximately" 1.3Liter. If it's hard to get all of the pot carbonate to dissolve (sounds like a possibility) i'd be tempted to make up half strength part B and use 2x as much (as I do with PMK, since I found it impossible to get the full amount of metaborate to dissolve in the required amount of water)

From my perspective there are advantages to expressing the formula for Stock Solution B as it presently is, and there are advantages to doing it the way you suggest. However, if I change the way the formula is expressed at this point in time I will get about 500 email messages over the next six months asking me to explain the discrepancy, and since I answer all my email you can see the problem. However, what you propose makes perfect sense and if it is more convenient for you to mix this way by all means do so.

I don't know how to explain why some people have difficulty in getting 1000g of potassium carbonate to go into solution in 1000ml of water. But I think the secret is to add the carbonate to the water very slowly, with constant stirring. It never takes me more than a couple of minutes to get it all into solution when I add it this way.

sanking · Oct 11, 2003

Black Dog said:
vvg article-excellent intro but covers plenty of ground as well. You mention using hypo clear btw-won't the sulfite in this remove some of the stain?

No, I tested this. Negatives that are cleared with 1% sulfite show no decrease in the level of stain.

jbrodkey · Oct 11, 2003

In your article you speak of streaking and pressure marks. To be clear, is this streaking increased or decreased film density? I assumed that since the cure is to load the film wet so that there "is a transfer of chemicals on the base of the film", that the streaks would be decreased density due to less developer action. Is that right?

Ole · Oct 11, 2003

sanking said:
I don't know how to explain why some people have difficulty in getting 1000g of potassium carbonate to go into solution in 1000ml of water. But I think the secret is to add the carbonate to the water very slowly, with constant stirring. It never takes me more than a couple of minutes to get it all into solution when I add it this way.

My guess is that they take 1 kg potassium carbonate and try to make 1 liter finished solution, instead of combining 1 liter of water and one kilo potassium carbonate...

It's no problem at all dissolving it - but then again I "cheat" and use a magnet stirrer!

matt.s. · Oct 11, 2003

Thank you for your article Sandy. I have been struggling to find an ideal developer for sheet film for a while. I use Fortepan 200 in 8x10 and have tried it in D-76, DK-50, HC-110, ABC pyro and Rodinal all producing good, but not great results for enlarging. I have tried PMK in 120 a few years ago and loved the sharpness but could not stand the muddy highlights it often produced with vc papers. Graded papers were fine but not readily available here in Australia anymore.

Yesterday I decided to mix up some Pyrocat-HD and processed some test sheets of 8x10 Forte 200 rated at EI:100 for 16 minutes at 20 degrees. The results were fantastic. The rich brown stain noticably different from that of PMK. I enlarged a small section of the neg about the size of a 120 neg up to 8x8 inches. The sharpness and lack of visible grain is quite incredible. Highlight tones are silky smooth and luminous whilst the midtones are rich with excellent separation.

It appears that I should be able to make enlargements from 8x10" negs up to 30x40 inches in size without a problem. This is exactly what I have been looking for.

Thank you so much for the work& time you have put into researching & publicising your formula.

Regards,

Matthew Stanton

MikeK · Oct 12, 2003

Sandy:

great article and I developed my first film (Classic Pan200 in 120 roll film) and the results look good.

I do have a question whether Sodium Carbonate could be substituted for Potassium Carbonate. My Dignan book states they are interchangeable and I could use 90% less Sodium Carbonate.

The reason I ask is I have tons of Sodium and only a few hundred grams of the Potassium.

- Mike

sanking · Oct 12, 2003

MikeK said:
Sandy:

great article and I developed my first film (Classic Pan200 in 120 roll film) and the results look good.

I do have a question whether Sodium Carbonate could be substituted for Potassium Carbonate. My Dignan book states they are interchangeable and I could use 90% less Sodium Carbonate.

Mike,

The answer is yes. If you look back at the article you will see that I give instructions for mixing both Stock Solution B and the working dilutions with sodium carbonate in place of potassium carbonate. If you mix these solutions as described sodium carbonate will give identical results to potassium carbonate. I recommend potassium carbonate only because of the convenience factor of the dilution.

Sandy

MikeK · Oct 12, 2003

<start of brain cramp>If you look back at the article you will see that I give instructions for mixing both Stock Solution B <brain cramp still active>

Another amazing senior moment. I printed out your article, took it to bed and read it last night. Made a couple of notes including what I said in my post, and I missed your commentary completely.

Oh well, better increase my dose of Geritol

- Mike

doughowk · Oct 13, 2003

Tried Pyrocat-HD this weekend. Went on a LF group photo-outing Saturday morning to a coquina stone beach area. Developed negs that night & next morning in 2:2:100 solution. The Forte 400 received 9 min development. They were very thin & printed on Azo with 4 sec exposure. The Agfa APX 100 dev for 15 mins & printed on Azo with 10 sec exposure - better looking neg. Also developed some negs in Diafine as comparison. The latter produced a denser neg at least for Azo printing. Still up in air as to what developer to settle on.<br>
One question: how long can I use working solution of Pyrocat-HD ( time or # of negs)?

jbrodkey · Oct 13, 2003

In the article it speaks of streaking and pressure marks. To be clear, is this streaking increased or decreased film density? I assumed that since the cure is to load the film wet so that there "is a transfer of chemicals on the base of the film", that the streaks would be decreased density due to less developer action. Is that right?

sanking · Oct 13, 2003

doughowk said:
Tried Pyrocat-HD this weekend. Went on a LF group photo-outing Saturday morning to a coquina stone beach area. Developed negs that night & next morning in 2:2:100 solution. The Forte 400 received 9 min development. They were very thin & printed on Azo with 4 sec exposure. The Agfa APX 100 dev for 15 mins & printed on Azo with 10 sec exposure - better looking neg. Also developed some negs in Diafine as comparison. The latter produced a denser neg at least for Azo printing. Still up in air as to what developer to settle on.<br>
One question: how long can I use working solution of Pyrocat-HD ( time or # of negs)?

First, the working solution of Pyrocat-HD is to be used once and discarded. I f I don't make that clear in the artilce I need to do so.

Second, what do you mean by density. Overall density results primarily from exposure, not development. Negatives that are described to me as very thin sound like they did not get enough exposure. If by density you mean contrast, or density range, this is a question of development. The 2:2:100 dilution of Pyrocast-HD if used for the correct time and temperature will give you plenty contrast for AZO printing. I can tell you for sure that your develoment time for Forte 400 is too short. You need at least 14-16 minutes to develop the CI needed for AZO.

sanking · Oct 13, 2003

jbrodkey said:
In the article it speaks of streaking and pressure marks. To be clear, is this streaking increased or decreased film density? I assumed that since the cure is to load the film wet so that there "is a transfer of chemicals on the base of the film", that the streaks would be decreased density due to less developer action. Is that right?

You would be right to assume that with BTZS tubes the pressure marks would result in areas of decreased stain from lack of developer action. Since this is on the base side of the film it may not be very noticeable, but it will make a lot of difference if printing with a UV sensitive process.

There is another kind of pressure mark that is caused by the ribs on print drums when these are used to develop film. This kind of mark may actually result from increased developer action as it speed up to flow over the ribs.

andrewfrith · Oct 13, 2003

earlier, someone mentioned to get a 1000ml of Solution B, they would use 769g of Potassium Carbonate instead of 1kg + 1000ml of water which would end up with 1.3L of solution. So, if i wanted to end up with 1L of solution B would i mix 769g of Potassium Carbonate with 769ml of water to end up with 1L of solution. i know its kinda splitting hairs but for me i use 1L storage bottles so 1L would work out better for me...

-andrew

Ole · Oct 14, 2003

andrew,
I use 100ml storage bottles. I only premix part A, then mix 10ml part A with an amount of water in which I've dissolved 7.7g potassium carbonate for a 1:1:amount mix.

So 1 liter water would be 1:1:100, ½liter 2:2:100. Saves me a bottle...

doughowk · Oct 14, 2003

A novice's question - how to read the graphs for individual films on page 4 of your article? For Azo printing, you should aim for a CI (contrast index) of .7 - .75. Figure 11 for Forte 400 would suggest a development time of 8-9 minutes to reach target CI. In earlier comment, though, "your develoment time for Forte 400 is too short. You need at least 14-16 minutes to develop the CI needed for AZO." I'm confused.<br>
My 15 min dev time for Agfa APX 100 seemed about right judging solely from print results.

Francesco · Oct 14, 2003

Doug,

I think that the chart you were referring to is for Fortepan 400 using a 2:2:100 dilution. To print with AZO I believe a 1:1:100 dilution for developing the negative is recommended. Unfortunately, a chart with Fortepan 400 using 1:1:100 is not included. However, if you scroll further down and look at the Ilford HP5 chart with 1:1:100 dilution, you will see that a CI of 0.7 to 0.75 corresponds to roughly 16 mins (not that Fortepan 400 and HP5 are the same but it is close enough I would think).

Francesco · Oct 14, 2003

Doug, I meant to say FP4.

sanking · Oct 14, 2003

doughowk said:
A novice's question - how to read the graphs for individual films on page 4 of your article? For Azo printing, you should aim for a CI (contrast index) of .7 - .75. Figure 11 for Forte 400 would suggest a development time of 8-9 minutes to reach target CI. In earlier comment, though, "your develoment time for Forte 400 is too short. You need at least 14-16 minutes to develop the CI needed for AZO." I'm confused.<br>
My 15 min dev time for Agfa APX 100 seemed about right judging solely from print results.

Doug,

You read the chart correctly, but the only chart included for Forte 400 is one based on UV reading and it is intended is calculating negative development times when printing with alternative processes that use UV light to expose. The charts that end with the word BLUE should be used for silver printing, incluidng AZ0. Unfortunately I have not run any tests of Forte with Blue light so there is no chart in the article that matches Forte to AZO printing. However, by simple comparison to similar high speed films for which Blue light tests were made I determined that about 14-16 of development wold be needed to reach the CI of about .75 needed for AZO.

juan · Oct 14, 2003

My question concerns development by inspection. The article says folks are using an amber safelight to DBI, as the brown stain is difficult to see with the traditional green safelight. I thought that on this forum or the Azo forum folks said the amber safelight fogs and that a red safelight is the proper one to use.
What are you DBI folks using?
juan

sanking · Oct 14, 2003

Francesco said:
Doug,

I think that the chart you were referring to is for Fortepan 400 using a 2:2:100 dilution. To print with AZO I believe a 1:1:100 dilution for developing the negative is recommended. Unfortunately, a chart with Fortepan 400 using 1:1:100 is not included. However, if you scroll further down and look at the Ilford HP5 chart with 1:1:100 dilution, you will see that a CI of 0.7 to 0.75 corresponds to roughly 16 mins (not that Fortepan 400 and HP5 are the same but it is close enough I would think).

I think that the 2:2:100 dilution is best for AZO printing with most films, certainly if you are developing for SBR of 7 and below. In the Blue light charts the most similar film to Forte 400 is Ilford HP5+ so I would recommend using these times as a guide for developing Forte.

Sandy

Donald Miller · Oct 14, 2003

chrisl · Oct 14, 2003

A little late to the party. I too just shot some 4x5 in a workshop at Mt. Shasta last week, and decided to try PMK in my Unidrum processor. Bought the pre made Photographers Formulary PMK, still all unopened...and now I read that Pyrocat HD is a better choice for rotary processing and VC paper? Just my luck.lol

Great article Sandy!
Chris

sanking · Oct 15, 2003

chrisl said:
A little late to the party. I too just shot some 4x5 in a workshop at Mt. Shasta last week, and decided to try PMK in my Unidrum processor. Bought the pre made Photographers Formulary PMK, still all unopened...and now I read that Pyrocat HD is a better choice for rotary processing and VC paper? Just my luck.lol

Chris,

Although I believe you will get in the long run more consistent results with Pyrocat-HD than PMK in rotary processing don't discard the PMK. It is an excellet developer and if you follow the same directions I give for rotary processing with Pyrocat-HD you should get good resutls in the Unidrum. The only thing I would add to the instructions would be that the initial pre-soak should be in a slightly alkaline solution for PMK. You could get this by adding about 1/2 of a teaspoonful of sodium carbonate or sodium metaborate per liter of pre-soak water.

philldresser · Oct 15, 2003

Sandy

You mention in your article to mix the Phenidone into a paste with Isoprophyl Alcohol, so I popped into a big pharmacy in the city this morning. I asked for Isoprophyl Alcohol and got some very funny looks and questions about why I wanted it and had to ask the Pharmasist.The reply came back "We don't sell it, maybe you should try at the Car Accessories shop" ???? "OK, do you have any rubbing alcohol instead"? I replied. They sold me a bottle? Go figure

Phill

sanking · Oct 15, 2003

philldresser said:
Sandy

You mention in your article to mix the Phenidone into a paste with Isoprophyl Alcohol, so I popped into a big pharmacy in the city this morning. I asked for Isoprophyl Alcohol and got some very funny looks and questions about why I wanted it and had to ask the Pharmasist.The reply came back "We don't sell it, maybe you should try at the Car Accessories shop" ???? "OK, do you have any rubbing alcohol instead"? I replied. They sold me a bottle? Go figure

That is very strange. All of the local Pharmacy stores (CVS, Eckherd, etc.) here in South Carolina have Isopropyl Alcohol on the shelves, clearly marked. I think you can get it in 70% or 91% strength but that makes no difference for the mixing. What I use is a straight 91% Isopropyl Alcohol sold by the quart at CVS. Rubbing alcohol has some extra stuff in there but I think it will not harm the formula.

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