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Philippe Gauthier
27-Jun-2004, 21:26
I currently do silver gelatin enlargements in 4x5 and cyanotypes/vandykes in 4x5 and 8x10. My alt process prints usually lack contrast, however, because my negatives are processed with silver printing in mind. Also, I use HP5+, which has a limited maximal contrast, I understand.

As I don't intend to change film, for several practical reasons, I'm tempted by Pyrocat-HD, which is said to produce negatives that behave differently under normal and UV light. The same sheet could then hopefully be printed by silver and alt processes.

I currently expose my HP5+ for EI 250 and tray process it in HC-110, dilution B, for 6 minutes (instead of the recommended 5). I don't have a densitometer, but my negatives normall print with a grade 2 filter on MC paper. I'd like to reach a similar density with Pyrocat-HD. I recently bought a rotary processor (Unicolor), which is one of the reasons why I'd favor this particular pyro formola over the others.

Now, my questions.

1. Is it reasonable to expect dual purpose negatives from HP5+ that would print on grade 2 paper and that would also yield excellent to good contrast with alt processes?

2. Can you offer a starting point for processing, keeping in mind the density I usually get and that I'd like to maintain?

3. What's the practical difference between 1:1:100 and 2:2:100 dilutions and why would you use over another?

4. Ordering the ready mixed product in the US is expensive, while I have a fine chemical supplier with low prices almost next door. Anything I should know before I mix my own Pyrocat-HD, apart from the obvious advice not to breath the pyro dust?

5. Anything else I should know?

sanking
27-Jun-2004, 22:23
Considering Pyrocat-HD for dual purpose negatives

"I currently do silver gelatin enlargements in 4x5 and cyanotypes/vandykes in 4x5 and 8x10. My alt process prints usually lack contrast, however, because my negatives are processed with silver printing in mind. Also, I use HP5+, which has a limited maximal contrast, I understand.

As I don't intend to change film, for several practical reasons, I'm tempted by Pyrocat-HD, which is said to produce negatives that behave differently under normal and UV light. The same sheet could then hopefully be printed by silver and alt processes.

Now, my questions.

1. Is it reasonable to expect dual purpose negatives from HP5+ that would print on grade 2 paper and that would also yield excellent to good contrast with alt processes?"

Yes.

2." Can you offer a starting point for processing, keeping in mind the density I usually get and that I'd like to maintain?"

Use the 1:1:100 dilution of Pyrocat-HD. With processing for 14 minutes at 72 degrees F will give you negatives with a DR of approximately 1.05 for normal silver gelatin processing, and about 1.70 for Pt/Pd. with UV light.

3. "What's the practical difference between 1:1:100 and 2:2:100 dilutions and why would you use one over the other?"

The 2:2:100 dilution is much more energetic and is recommended for alt processing with times of around 8-10 minutes, and for subject lighting conditions of very low contrast.

4. "Ordering the ready mixed product in the US is expensive, while I have a fine chemical supplier with low prices almost next door. Anything I should know before I mix my own Pyrocat-HD, apart from the obvious advice not to breath the pyro dust?"

I recommend buying the chemicals chez vous and mixing a la maison or maximum economy. Assuming your donít breath or eat the stuff there is little danger in mixing.

5. Anything else I should know?

--Philippe Gauthier, 2004-06-27 08:26 PM

Not that I can think of. Let me know if you have further questions.

Andre Noble
27-Jun-2004, 22:55
Off topic somewhat,

Just tried Pyrocat HD for 1st time today. Used Jobo 2500 tank with Jobo CPP2 rotary processor set to lowest rotation speed possible. Was pleasantly suprised at clean negs and the low general stain (film base + fog) levels compared to my WD2D+ hand inversion development.

Question for Sandy King, so is the ~14 minutes dev time a good general recommendation starting point for traditional B&W films such as APX 100?

Jim Galli
27-Jun-2004, 23:16
Philippe, Funny, I just finished my first batch of Efke 100PL in PCat HD. I've been using it exclusively since days after Sandy first posted his article on Unblinking Eye.com. I ordered the chems the day I read the article and have been nothing but pleased since the first batch. I mixed it easily just following Sandy's instructions in the article. Nothing could be simpler. I'm now about half way through the fourth batch I've mixed. Very consistent from batch to batch. I come with a slightly different background though having spent about 4 years trying to resolve problems with PMK. The "Pyro" had me hooked but I was constantly getting weird edge effects. Like I could clip 1/4" all the way around the negs and throw that much away because it was un-useable. The PCat not only resolved all of that it re-introduced me to several films I had dismissed as too bland including HP-5 and Tmax 400. Now there is grade 2 and then there is grade 2. Years ago I began tailoring my negs to a generic offering that Freestyle Sales Co. called "Europes Finest warm tone #2" It was actually somewhere between #1 and 1 1/2. Most people hated it but I loved the way my looong toned negs looked on it in Ansco 135 and Selenium. So that got me started on making negs with a very long scale that I have to force to go on a #2 paper. But all the better for the alternative processes. All that to say that on Sandy's charts I usually shoot for about 7.5 development and so far it's been dead on. The Efke 100 I did tonight would have normally been a N-1 or more. I souped them for 8 minutes in 2:2:100 in the Jobo at 72?+ degrees and they are GORGEOUS! I'm rambling, but all this to say give the stuff a try, I'll bet you'll be very pleased.

Pete Caluori
28-Jun-2004, 06:34
Philippe, I don't generally use HP-5+, but other films in Pyrocat can yield dual purpose negatives. I'm a firm believer that for optimal results you should craft the negative for the intended process, but a Pytocat developed negative can yield excellent results for both. Films that I have used with good result are Kodak Tmax-400 (TMY) Efke PL100 and Ilford FP-4+ & Photo Warehouse 125. I have Pyrocat developed TMY negatives that make beautiful Van Dykes and print without filtration, using my dichro enlarging head, onto Ilford warmtone paper.

Regards, Pete

sanking
28-Jun-2004, 07:12
I need to correct a mistake that I made in an earlier response to Philippe.

The suggested development time of 14 minutes for Pyrocat 1:1:100 and HP5+ will indeed give a negative with an effective DR of about 1.7 for palladium printing, but the effective printing density range for silver will be much higher than 1.05 with that time of development.

A better time for a dual purpose negative with HP5+ would be about 10 minutes at 72 degrees F. This will give a negative with an effective density range of about 1.05 for silver and 1.45 for Pt/.Pd. Printing in palladium with such a negative with require some form of contrast booster, of which the most popular and effective appears to be the Na2 method. Unfortunately there are so many variables involved in making dual purpose negatives that am hesitant to suggst development times for other films.

For those who may be confused as to how a negative can have a different effective printing density range for silver and Pt./Pd. have a look at the charts in my article at http://unblinkingeye.com/Articles/PCat/PCat3/pcat3.html. The curves and explanation in the article will also explain why Pyrocat-HD is a more effective developer than pyrogallol based developrs such as PMK and WD2D for making dual purpose negatives that will print in both silver and Pt./Pd.

Philippe Gauthier
28-Jun-2004, 08:22
Thank you very much for the answers so far. Yes, Sandy, I rencently read your article on the Unblinking eye. This is what introduced me to the idea to the almost unbelievable idea of dual purpose negs. It's a bit hard to believe that the same piece of film will have a different effective density of UV and white light, but I suppose that the Gods of photography have decided to make our lives a bit easier this time.

E. U. Eichhorn
28-Jun-2004, 09:00
I'll preface this question with I'm a rank amateur and I'm just looking for how to use pyrocat-hd with my omega d2 enlarger and regular old silver gelatin paper, but I'm confused about 1:1:100 v 2:2:100. On unblinkingeye.com figure 20 HP5+ is shown using 2:2:100 with BLUE meaning that for printing on silver gelatin with a non-UV light source you should use 2:2:100. But above, Sandy says that 2:2:100 is used for "alt processing" which I've always assumed was UV and pt/pd or something similar.

I've been developing HP5+ 120 roll film and 4x5 at 2:2:100 for 11 minutes @ 70 degrees and they come out pretty darn fantastic for printing on the papers I have tried. (Luminos Classic Warmtone and Ilford Multigrade for example.) They look good on AZO too. I've been doing tmax100 4x5 at 2:2:100 for 10 minutes @70 degrees and they print well too. Printing times are in the 10-15 second range usually.

So, I don't get it. Am I supposed to be using 1:1:100? Does that extra 2 degrees less of temperature really increase the development that much? (It is really hard to keep water above 68degrees in my basement at night, especially during winter.)

Thanks,

EU

sanking
28-Jun-2004, 10:08
The recommendation to use the 1:1:100 dilution for silver printing and 2:2:100 for alternative is made to provide the most reasonable development times for the two kinds of processes since they require negatives of different contrast. It is not set in stone and there are certainly many cases where one might be better off reversing the recommendation. But in general alternative printing requires negative of much more contrast than silver and the use of the 1:1:100 dilution would mean very long development times. On the other hand, with many films the very energetic 2:2:100 dilution gives development times that are too short to be manageable for silver printing.

I am surprised that you get negatives that print well in regular silver with 11 minute development time with the 2:2:100 dilution. My own tests show that this time would work well for AZO printing, which requires negatives with a DR of bout 1.55, but that the negatives would be much too contrasty for normal silver papers. But if the time it works for you that is the only thing that really matters.

Scott Killian
28-Jun-2004, 15:01
Sandy,

Have you or anyone else determined 1:1:100 development times for Efke 100 (PL100) for enlargement printing? I've seen many other films online, but haven't found this one.

Also, in my own 8x10 work, I've been using 2:2:100 with Efke 100 to print on Azo and I'm making the best prints I've ever made in my life. Far better than anything I previously did with ABC. Not once have I experienced uneven development or streaking (using homemade BTZS tubes). I'm not technically minded, I simply set shadows on zone 4 and find that 70% of my prints require grade 3 & a touch of water bath (the opposite was true when I used ABC). However, these negs are indeed a touch too contrasty for enlargement printing which I why I'm looking for times.

Hats off to Sandy for formulating a great developer!

sanking
28-Jun-2004, 22:54
Hi Scott,

Thanks for the nice comments about Pyrocat-HD.

I have done a fair amount of work with Efke PL 100, which I consider one of the best films available in large and ultra large format, both with the 1:1:100 and 2:2:100 dilution. And if one is interested in dual negatives for normal silver gelatin printing and Pt/Pd I would recommend a time of 10:30 at 72 degrees F for this film, using the 1:1:100 dilution. This time will give a DR of about 1.05 for silver gelatin printing, and 1.40 for Pt/Pd with UV light.

However, as far as I know there is no way to make a negative that will print well with both normal silver papers and AZO. Both processes are primarily sensitive to blue light so you do not get the benefit of stain that allows different effective printing contrast for silver and alternative printing. And, since you need a negative with a very high density range for AZO (about 1.50) there is virtually no way that you can print both AZO and normal silver gelatin papers (which need a negative DR of about 1.05) with the same negative.

For printing with AZO the 2:2:100 dilution that you are using is certainly the best. At 10 minutes of development I get a DR of about 1.55, which is perfect for AZO, and about 1.90 for UV sensitive processes that require a very high DR, such as albumen, salted paper and vandyke.

Scott Killian
29-Jun-2004, 06:25
Thanks Sandy, just what I was looking for. Completely agree about differences in density needed for Azo vs Enlargement. The times I was looking for are for my 120 negs which I enlarge. Standardizing on one film and developer for both my contact printing and my enlarging is a dream and it looks like it will work well.