Pyrocat-HD

philldresser · Feb 29, 2004

I have just finished a sample of 5x4 negs developed with Pyrocat-HD using minimal agitation and I am very pleased with the initial results.

I used the 1:1:150 dilution for 45 mins in BTZS tubes.

My observations(although not scientific) are as follows:
1. The negs seem to have stained more using this technique over my previous constant agitation runs but this might be subjective as I don't have a densitometer.
2. The negs are very sharp and fine grained

I also liked the long process as it allowed me to answer the phone, make the tea and read Black and White magasine whilst developing. I will now try and establish my personal film speed using the minimal agitation and incorporate this technique in my reportior.

Phill Dresser

Francesco · Feb 29, 2004

Phil, I use the 1:1.5:120 dilution (I tested quite a few of them) for all my minimal agitation negatives and my printing times are now between 30 to 60 secs on Grade 2 AZO.

sanking · Feb 29, 2004

philldresser said:
I have just finished a sample of 5x4 negs developed with Pyrocat-HD using minimal agitation and I am very pleased with the initial results.

I used the 1:1:150 dilution for 45 mins in BTZS tubes.

My observations(although not scientific) are as follows:
1. The negs seem to have stained more using this technique over my previous constant agitation runs but this might be subjective as I don't have a densitometer.
2. The negs are very sharp and fine grained

I also liked the long process as it allowed me to answer the phone, make the tea and read Black and White magasine whilst developing. I will now try and establish my personal film speed using the minimal agitation and incorporate this technique in my reportior.

Phill Dresser

Phil,

I just looked at data comparing the 1:1:150 dilution (minimal agitation) of Pyrocat-HD with the 2:2:100 dilution (rotary) with three films, FP4+, 400Tmax and 320TXP and there was virtually no difference in the level of stain with the two methods, either with Blue reading or UV reading. I had actually expected that the stain wold be much less with the minimal agitation procedure becaue of the fact that the film is still for so long in the developer so the the actual results were somewhat surprising.

Sandy King

philldresser · Mar 1, 2004

Sandy

That is interesting. The only differences in technique was a longer and more vigourous presoak (5 mins vig 5 mins stand) as I was keen to remove all AHL dyes. Also the comparison is totally based on a visual inspection. I have duplicate shot still undeveloped so I will do this using the normal agitation and compare these.

Phill

Donald Miller · Mar 1, 2004

I don't find the stain being the same in these two methods of development to be all that unusual. As I look at it, the material that is capable of containing proportional stain is the gelatin of the film emulsion. The amount of gelatin has not increased or decreased in the methods. Thus it would seem that the potential is to contain a given degree of stain.

sanking · Mar 2, 2004

Donald Miller said:
I don't find the stain being the same in these two methods of development to be all that unusual. As I look at it, the material that is capable of containing proportional stain is the gelatin of the film emulsion. The amount of gelatin has not increased or decreased in the methods. Thus it would seem that the potential is to contain a given degree of stain.

Donald,

However, HP5+ negatives developed in Pyrocat-HD 2:2:100 in trays have a lot less stain, for a given CI, than negatives developed in Jobo with fast rotary action, which clearly suggests that vigorous development and oxidation through air contact also play a role in staining, at least in non-image forming stain. I know this for a fact because I tested some negatives made by Clay Harmon using the two method of development. This fact, in the absence of other consderations, would have led me to believe that a negative developed completely submerged in the developer, with very limited agitation, would not experience the same level of oxidations, and would consequently have stained less.

I don't have a clear idea at this point why the supposition appears to be false.

Sandy

clay · Mar 2, 2004

Sandy:

I can't help but think that oxidation of the developer has something to do with staining. Anytime I pour out the spent developer from my Jobo and it is brownish-orange, then I can expect the negative to have quite a bit of visible staining, including some undesireable general staining.

I am beginning to wonder if saying 'rotary development' may be a little too imprecise to describe what may be going on. It seems to me that if you develop a sheet of 7x17 film in a homemade tube with a 3 inch diameter, then the film will spend a lot less percentage of time exposed to the air than if you develop 5 sheets of 8x10 film in a jobo expert drum, which has a much larger radius. Developer volume would also be a factor here in determining the amount of time the film spends in the developer versus out of the developer.

Yet another variable with the expert drums is the fact that they dribble developer like a water wheel and this would maximize the exposure of the developer to the air versus a single straight tube which would have more or less a fixed surface area of developer that is exposed to the air.

I guess the real test of this for someone with patience would be to tray develop some identically exposed film tests, and time it so that one stayed completely submerged, one spent about 1/3 of the time being hoisted into the air, and the other about 2/3 of the total time not submerged. I am willing to bet that there would be some noticeable differences in the staining.

If I could learn to develop in trays without scratching, I think I would probably end up doing that method, because it seems to me to provide the least general stain and the maximum image stain with most films. My jobo tests have certainly shown me that slowing the rotation speed is a big help, but rotary processed negatives still are not as 'clean' looking as the tray developed ones.

sanking · Mar 2, 2004

clay said:
Sandy:

I can't help but think that oxidation of the developer has something to do with staining. Anytime I pour out the spent developer from my Jobo and it is brownish-orange, then I can expect the negative to have quite a bit of visible staining, including some undesireable general staining.

Clay,

I definitely agree with you that a very great percentage of the b+f or non-image stain results from oxidation of the developer, and that more of it results from fast rotation. This can be controlled to considerable extent, as we have discusssed in the past, by adding extra sulfite to the working solution, if the additional b+f stain is a problem, as it certain can be with films such as Tmax 400, BPF, and to a slightly lesser extent TRI-X and HP5+. On the other hand films like FP4+, Delta 100 and 400 and Tmax 100 hardly develop any b+f stain at all, though they all develop some image stain to a varying degree.

The curiosity for me is why a sheet of film developed in a tube completely covered with developer and never in contact with the air would develop any b+f stain at all, especially since there is so little agitatin during develoment. And yet with minimal agitation I am seeing about the same level of b+f for film developed this way as with film developed with rotary agitation, *assuming that the two films are developed to the same CI.*

Sandy

clay · Mar 2, 2004

Could part of the reason be the large time difference between the methods? The deciding factors may be the surface area exposed to the developer AND the amount of time. With stand developing, you are developing for what, maybe 3-4X the time you would normally use for rotary tubes? Maybe there is some sort of natural oxidation that occurs in the solution. Isn't that the reason that we store the solutions as an A+B solution instead of mixing it all together? Jorge, you're the chemist here. Wouldn't the alkali start some natural oxidation once it was mixed with part A?

sanking · Mar 2, 2004

sanking said:
The curiosity for me is why a sheet of film developed in a tube completely covered with developer and never in contact with the air would develop any b+f stain at all, especially since there is so little agitatin during develoment.

Sandy

I meant to add to the above sentence the fact that when the developer is discarded after developing with the extrmeme minimal procededure there is almost no discoloration at all of the spent solution. The large amount of developer that is required to completely cover the film in a tube appears to almost entirely eliminate the discoloration I previously associated with oxidation. But with long development times there is still some b+f stain, even when the discarded developer has no apparent discoloration. This make me believe that there must be some other mechanism in play in addition to developer oxidation.

Sandy

Jorge · Mar 2, 2004

clay said:
Could part of the reason be the large time difference between the methods? The deciding factors may be the surface area exposed to the developer AND the amount of time. With stand developing, you are developing for what, maybe 3-4X the time you would normally use for rotary tubes? Maybe there is some sort of natural oxidation that occurs in the solution. Isn't that the reason that we store the solutions as an A+B solution instead of mixing it all together? Jorge, you're the chemist here. Wouldn't the alkali start some natural oxidation once it was mixed with part A?

Well, I am very confused by this thread as well as the one at Michael's forum. I always thought of stand development as a technique for lowering contrast, but Sandy and others are reporting full CI's with this technique.

Every time we introduce oxigen in the mix, we will have oxidation and as you correctly pointed out this is why we keep the two solutions apart, yet it seems Sandy is correct and there must me another mechanism. If I had to guess, I would say that the superadditivity mechanism is preventing developer oxidation, using all the available oxidation to regenerate the individual developing ingredients, thus the absence of discoloration in the solution. When we use robust agitation we are aereating both the film (with the left over developer on it) and the developer itself, and we get discoloration.

I am doing some portraits tomorrow, so I will experiment with one of the negatives with this technique, but I dont know if I have the patience to sit for 40 min waiting for the film to develop.

Jorge · Mar 2, 2004

BTW, with brush development I get little overall stain, for a .89 G bar I only get .25 b+f (UV), but then I think two factors are in play here, the film is always submerged and I use NaOH as the accelerator which requires a lower concentration to develop to the same CI as the Carbonate.

sanking · Mar 2, 2004

Jorge said:
BTW, with brush development I get little overall stain, for a .89 G bar I only get .25 b+f (UV), but then I think two factors are in play here, the film is always submerged and I use NaOH as the accelerator which requires a lower concentration to develop to the same CI as the Carbonate.

Jorge,

The b+f of log 0.25 is with Ilford FP4+ (or Photowarehouse ASA125), right? And with UV reading?

If so, this is fairly close to my own results with this film with regular Pyrocat-HD with the potassium carbonate accelerator.

Sandy

Jorge · Mar 2, 2004

Ah, sorry should have been more specific (I beleive this is twice I have done this to you.), the .25 is for TMY, for PhotoW I get somewhat higher, around .30 (UV) for high CI's. For low to moderate CI I get very low readings in the neighborhood of .12 to .18 (UV) for both films.

sanking · Mar 2, 2004

Jorge said:
Ah, sorry should have been more specific (I beleive this is twice I have done this to you.), the .25 is for TMY, for PhotoW I get somewhat higher, around .30 (UV) for high CI's. For low to moderate CI I get very low readings in the neighborhood of .12 to .18 (UV) for both films.

Jorge,

Curious, I get much lower b+f with Ilford FP4+ than TMY.

BTW, I spent the evening experimenting with a 25% sodium hydroxide B solution with Pyrocat-HD. I did tests at 1:1:100, 1:2:100, 2:1:100 and, 2:2:100, 4:1:100, and 4:4:100 4:1:100. I got the best results (in terms of maximum Dmax and minimum b+f) with the 2:1:100 dilution.

I don't see much differnce, if any, in terms of minimum b+f density between the sodium hydroxide and potassium carbonate, at equivalent best amounts, but the sodium hydroxide sure works better in developing contrast quickly with the low contrast films. I think it is even more effeperhaps e than ABC Pyro at the 1:1:1: 7dilutiion, though for sure I will need to run more test to veify this.

To balance the mixture at 1:1:100 I figure to adjust the Stock B Sodium Hyroxide solution to about 12%. Does that sound about right to you. I notice that your working solution is 1:1.5:100 with a 10% Stock B sodium hydroxide solution, which sounds very close to what I came up with as the best mix of the two stock solutions.

Sandy

Eric Rose · Mar 3, 2004

Now for something not so technical. I just developed a roll of TX 320 using a half filled bottle of solutions A and B that had been sitting there for at least a year. Mixed them up 1.5:1.5:100 and dev for 15min's. Guess what? They turned out beautiful! I had previously developed it's sister roll in HC110 dil B and the PyroCat HD negs look and print much better. Mind you it was one of those sweeping prairie landscapes with lots of puffy clouds that PC-HD seems to love.

Just thought I would throw this in as it seems everyone thinks the shelf life is pretty limited.

sanking · Mar 3, 2004

EricR said:
Now for something not so technical. I just developed a roll of TX 320 using a half filled bottle of solutions A and B that had been sitting there for at least a year. Mixed them up 1.5:1.5:100 and dev for 15min's. Guess what? They turned out beautiful! I had previously developed it's sister roll in HC110 dil B and the PyroCat HD negs look and print much better. Mind you it was one of those sweeping prairie landscapes with lots of puffy clouds that PC-HD seems to love.

Just thought I would throw this in as it seems everyone thinks the shelf life is pretty limited.

Eric,

I am really glad that you posted this information. When I originally introduced the Pyrocat-HD formula I was very conservative in the estimated stability of the stock solutions because at the time I had only about six months of experience in working with the final formula. So I gave an estimated shell life of 1/2 of that time, i.e. three months, to be on the safe side. And the original formula was for only 100ml of Stock A and B solutions, as some might recall, in the e anticipation that most users would need to mix again in three months or less.

Now that several years have passed, and I have had a lot of experience with the keeping qualities of the stock solutions, I know for a fact that the shell life in partially full bottles (assuming mixing with distilled water) is at least two years, and perhaps even more. But I have been reluctant to state this fact without verification from actual work in the field by others. So for the reality check I thank you.

Sandy King

Jorge · Mar 3, 2004

sanking said:
To balance the mixture at 1:1:100 I figure to adjust the Stock B Sodium Hyroxide solution to about 12%. Does that sound about right to you. I notice that your working solution is 1:1.5:100 with a 10% Stock B sodium hydroxide solution, which sounds very close to what I came up with as the best mix of the two stock solutions.

Sandy

Sounds about right, I guess if you do the 12% solution you would need a 1:1:100 concentration to get similar results as 2:2:100 when using carbonate accelerator. For simplicity sake I settled on 1:1:100 using NaOH 10% and giving a little bit more developing time to acheive the same CI. I think I mentioned this, but IMO this combinatin is not good for long scale negatives as the times get really short.

sanking · Mar 3, 2004

Jorge said:
sanking said:

For simplicity sake I settled on 1:1:100 using NaOH 10% and giving a little bit more developing time to acheive the same CI. I think I mentioned this, but IMO this combinatin is not good for long scale negatives as the times get really short.

Click to expand...

Yes, that is obvious from my tests. But bear in mind that I am looking for a specific solution with these tests, i.e. how to get enought contrast from low contrast films like BPF, JandC Classic, HP5+, and even 320TXP when used in low contrast lighting and intended for printing with alternative processes. You must have a developer with a lot of energy to get past the relatively low Gamma Infinity range of these films with standard strength developers. Even the regular 2:2:100 dilution of Pyrocat-HD, which is a very energetic developer by most standards, comes up a bit short with these films in these situations.

Just looking at the data suggests that a 2:2:100 working dilution of Pyrocat-HD using a 10-12% sodium hydroxide Stock B solution in place of the regular 75% potassium carbonate Stock B will solve the problem.

I think this is an important consideration because in my experience a very large part of ULF work is done for alterntive printing, with low contrast films in low contrast lighting.

Sandy [/i]

Jorge · Mar 3, 2004

I agree, for increasing contrast the sodium hydroxide activator is much better.

BTW I tried the semi stand developing with NaOH and I would not recommend it for this technique. The negative still printed beautifully but it was bullet proof, with a 6.2 SBR and 45.8 min developing the neg had 3.11 for the white parts with detail and 2.42 density for the middle gray (UV), took 1000 units in the Nuarc to print..lol....still, sharpeness, skin tone and tonal transition were beautiful...the lady was very happy...

Donald Miller · Mar 4, 2004

Jorge said:
I agree, for increasing contrast the sodium hydroxide activator is much better.

BTW I tried the semi stand developing with NaOH and I would not recommend it for this technique. The negative still printed beautifully but it was bullet proof, with a 6.2 SBR and 45.8 min developing the neg had 3.11 for the white parts with detail and 2.42 density for the middle gray (UV), took 1000 units in the Nuarc to print..lol....still, sharpeness, skin tone and tonal transition were beautiful...the lady was very happy...

Jorge,

What was your shadow density on the neg?

Jorge · Mar 4, 2004

Shadow with detail was 1.49, and "zone I" was .84 all in UV readings.

Donald Miller · Mar 4, 2004

Jorge,

Thanks for the information.

Donald Miller

philldresser · Mar 5, 2004

Jorge said:
... took 1000 units in the Nuarc to print..lol....

Careful Jorge, you might cause another North American blackout

Phill Dresser

Pyrocat-HD

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