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MaxPyro

Gainer: You should be helping Ralph on his new edition! Great stuff about the developers. Even if some of us don't have the inclination to try your mixtures, your posts are very helpful and instructive. Thanks for taking the time and effort to help educate us. Very much appreciated on this end.

Ed
 
gainer said:
Ian. how effective is "effectively"? Is it one of those patents that seeks to cover all possible combinations of pyro and Metol? How about a Pyro-Metol-Ascorbic acid-TEA single solution concentrated staining developer?
Click to expand...


Hi Pat,

How about this single solution Pyro+metol+ascorbic, the fundamentals of which were strongly inspired by Gainer? I mixed it up directly in TEA with a hot plat stirrer at about 150F.

Pyro-Uno
TEA 85 ml
Ascorbic acid 2 g
Pyrogallol 5 g
Metol 1 g

TEA to make 100 ml

Mix chemicals in order listed. Will dissolve easily with a hot plate stirrer at about 150F.

Working Solution: 1:50 to 1:200
Starting point development time at 1:100 is 10-14 minutes with rotary (continuous) processing.

I have done some BTZS testing of the developer and will post a chart later after plotting the results.

The amount of total reducer in Pyro-Uno in a liter of working solution at 1:100 is about the same as that of Pyrocat at 1:1:100, and this should give good acutance.

Sandy King
 
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Sandy: What is TEA? I assume, of course, that it is not drinking tea :}...any special concentration or componenets in the TEA?

I look forward to the BTZS data.

Ed
 
Mahler_one said:
Sandy: What is TEA? I assume, of course, that it is not drinking tea :}...any special concentration or componenets in the TEA?

I look forward to the BTZS data.

Ed
Click to expand...


Ed,

TEA is Triethanolamine. See http://en.wikipedia.org/wiki/Triethanolamine

Reducers mixed in TEA are very long lasting, and when mixed with water an alkaline solution of about 9.8 is formed that is fairly ideal for pyrogallol.

Gainer's PC-TEA is a one solution developer made up of phenidone + ascorebic acid in TEA. You just mix it with water for use.

Sandy King
 
I tried a similar approach using catechol, but TEA could not supply the pH of the Potassium carbonate solution. I haven't played with DEA (diethanolamine) yet, but Kodak did in HC-110. Don't mess with MEA. You can get a brochure that tells all you want to know about all three from Dow.com.
 


Speaking of pH, a 1:100 dilution of the Pyro Uno formula I mentioned earlier is pH 9.4 with my meter, a tad lower than what I would expect to get with PMK using sodium metaborate.

Sandy King
 
If you expected to use 1:100 a lot, you could add more TEA to the mix. Diluting the concentrate half and half with TEA might do it. Then, of course, 1:50 becomes 1:100 with as much TEA as the usual 1:50. OTOH, 1:75 or 80 might, by virtue of slightly reduced pH, give you what you would expect from 1:100.

I did a trial of my above formula on HP5+: 12 minutes @ 70 F. No printing filter on Kentmere VC.
 

Attachments

  • PMC-TEA HP5+.jpg
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Forgot to say my example was with1+50 dilution.
 
Mahler_one said:
Sandy: What is TEA? I assume, of course, that it is not drinking tea :}...any special concentration or componenets in the TEA?

I look forward to the BTZS data.

Ed
Click to expand...


Ed,

The BTZS tests show that the Pyro Uno formula is a bit too energetic for my taste at the 1:100 dilution, where I would like to calibrate it, so I am going to tinker a bit more with the mix before making it final and posting any curve data. To the extent possible I would like to adjust the formula so that development times are very close to those of Pyrocat-HD at 1:1:100. This will make it much easier for me to carry out other tests for sharpness and grain.

Sandy
 
I just reexamined Pyro Uno and saw that you would use 10 grams of Metol per liter. Pyrocat MC only uses 2.5. That would probably be a good place to start tweaking.
 
gainer said:
I just reexamined Pyro Uno and saw that you would use 10 grams of Metol per liter. Pyrocat MC only uses 2.5. That would probably be a good place to start tweaking.
Click to expand...


That is a good suggestion. But first I am going to follow your first suggestion and add about 30% TEA to the solution that I already have mixed up. In fact, I am doing that right now and will run a new test soon. If this does not work I will consider the reduction in metol for the next batch.

Sandy
 
Thanks to both of you. A few questions when you have completed the testing!

1. Any "advantage" to PyroUno over Pyrocat in its various incarnations? Over any of the other Pyro formulations?

2. Might you write down the "final" formula(s) when the curves are completed?

Interesting work, and once more, a very, very sincere thanks to both of you for helping all of us.
 

Ed,

First, I am just having some fun along with Gainer in seeing what we could come up in terms of a single solution pyro staining developer that uses pyro + metol + ascorbic. I tend to think that if I adjusted the formula so that it had about as much reducer in it as Pyrocat, and it was about equally energetic, it should perform about the same. But whether that in fact is the case only real results will tell.

Second, yes, when I have the final formula I will write it all down, with curves, so anyone who wants to can play with it. That might come soon, or it might take a while. One never knows for sure where this stuff will lead!!

Sandy
 
Well, a single solution would be nice...thanks Sandy and Gainer.
 
The stain color of Pyro might be preferred over catechol for some purposes. It is nice to have a choice, especially if both developers handle about the same, and can last a long time on the shelf. Sandy can tell you more about the effects of the stain colors on the various possible printing methods and papers.
 

Basically, the stain of pyrogallo based developers gives greater highlight compression with VC papers than that of pyrocatechin based developers. All things considered, if I were printing primarily with VC papers, I would prefer a pyrogallol based developer for scenes of very high contrast, but a pyrocatechin based developer for medium and low contrast scenes.

For printing on graded papers, or with alternativ processes, the stain of both Pyrogallol and Pyrocatechin based developers adds printing contrast, the latter a bit more than the former.

A one solution developer is simple to use in that all you need to do is mix the developer with water to form a working solution, but there are also some disadvantages in that you can not change the relationship of reducer to accelerator, and it is also not possible to use one solution developers with two bath development.

Sandy King
 
510 pyro is a single solution developer

TEA 75 ml
Ascorbic acid 5g
Pyrogallol 10g
Phenidone .25 g
TEA to make 100 ml

Brown stain

Mike
 
sanking said:
there are also some disadvantages in that you can not change the relationship of reducer to accelerator, and it is also not possible to use one solution developers with two bath development.

Sandy King
Click to expand...

That is true if you restrict the definition to mean that no image is developed in the first bath, but the first 2-bath developer I heard of and used was D-23 with a borax afterbath. I quit using it when I made my first densitometer and found no significant difference in characteristic curves between D-23 as one or two bath developer.

One could certainly use propyene glycol as solvent and add TEA or any other base that suits the psyche. It might be a good idea to do some experiments to see if the 2-bath idea is worth using with a pyro developer. Things have changed a lot since my first experiments. Film speeds were still ASA and emulsions were much thicker. I remember having no difficulty causing reticulation in those days, and sometimes dried film was like a clock spring.
 
mikebarger said:
510 pyro is a single solution developer

TEA 75 ml
Ascorbic acid 5g
Pyrogallol 10g
Phenidone .25 g
TEA to make 100 ml

Brown stain

Mike
Click to expand...

You could also use a gram or so of p-aminophenol in place of Phenidone if you like.
 
But then it would be 5101 Pyro...
 
One of the primary objections I have with the single soluton developers mixed in TEA is that unless you keep the solution heated the viscosity of TEA at room temperature makes it difficult to measure small quantities of the developer accurately. I thought of mixing in glycol 1:1 but that wound up reducing the energy of the devleope quite a bit.

Any ideas about something that would mix well with TEA and reduce itsviscosity and maintain the pH that is provided by TEA without reducing shelf life?

Sandy King
 
maybe just using a syringe for measuring? works fine for hc110.
 
phritz phantom said:
maybe just using a syringe for measuring? works fine for hc110.
Click to expand...

I am using a syringe for measuring now. However, when measuring small amounts like 1-5 ml I have to first pour the solution into a small beaker, then pull out the needed amount with a small syringe. There is a fair amount of waste measuring this way.

Sandy King
 

and one of those corks with a hole in it?

like here: http://www.covingtoninnovations.com/hc110/hc110n.jpg

(the last smart interjection from the nosebleed section)
 
I use either 5 0r 10 ml hypodermic-style syringes that you can get at the druggist's. If the mouth of the container is too large for the stopper that comes with the syringe, cut a 1/2 inch hole in the cap. I can even use the large containers that powders from PF come in. I use the hole cutters from a set of gasket cutters you can get at auto supply places. Lay the cap screw side up on a block of wood and whale away at the cutter with a hammer until it cuts through.
 
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