Pyrocat question...

[Christopher Barrett]

I'm new to Pyro and am using PyrocatMC in my Jobo with Fuji Acros. Though I'm really pleased with the feel of my negs, I had to drop my speed considerably. Acros runs pretty true to 100 in XTol but feels more like 25 in my Pyro routine. I'm doing 1:1:100 for 10 minutes at 20°C. I just did a speed test, lighting a grey card with strobe. My Zone I neg at ISO 32 returned a density of .05 over B+F, which is still thin, so an ISO of 25 seems closer to true for me. My Zone I to Zone VIII showed a density diff of 1.07, so I'm gonna bump my dev time up 25% and go again.

Thoughts? Advice?

Thanks!
-CB

[xkaes]

I haven't used a pyro developer in years, but it sounds like you know what you are doing and are on the right track.

There are two "pyros" out there and both are developing agents with similar chemical structures:

-- Pyro, AKA Pyrogallic acid, Pyrogallol

-- Pyrocatechin, AKA Catechol, Pyrocatechol, ortho-dihydroxybenzene

I've only used the later and don't know the differences in effects. Perhaps other do. But be careful, at least the latter is a severe irritant -- probably th former as well.

FYI, if anyone on this board wants an ounce of the latter, I can send it to you for the price of shipping.

[Alan9940]

I've used Pyrocat-HD for many years to develop several different films and fairly recently started experimenting with -MC and I've never measured that much loss in film speed. Is the stock developer fresh? Are you running the Jobo at its slowest speed?

[koraks]

I haven't done any densitometry, nor do I use Acros, but I'm very surprised at the apparent 2 stop speed drop. I use pyrocat hd quite a lot and have never noticed a speed drop compared to box speed with the films I have used with pyrocat so far. Since the mc and hd variants should respond quite similar and pyrocat isn't noted for a large speed drop, I suspect something odd is going on here.

[David Schaller]

I use Pyrocat HD with trays or hand inversion, and I get Acros @80, just as I do with D-76. I do develop at 70F though. I use the 1:1:100 Pyrocat hd in glycol from PF.

[alanbutler57]

I've run into this before with HD and suspect I'm just not using enough solution.

Somewhere I read Sandy King; who developed Pyro HD, recommends 75ml of 1:1:100 per 4x5 neg, but I've always used 600 ml in my Jobo to develop 12 images at a time, and usually had to "push" in the scanner.

When I recently started playing with double sided X-ray film I cut back to 4 negatives per run and both green (ISO 100) and blue (ISO 50) look about right for the exposure. Just a visual observation combined with reading the histogram on the scanner.

[Christopher Barrett]

Hmm, maybe I'll contact the Formulary and see what they think. I like the look of the Pyro Negs but a two stop speed drop is craziness.

[Larry Gebhardt]

I suspect you don't have enough active developer for the area of film being developed. It's been a while, but I believe I ran into this when I first started using pyrocat. I use 2+2+100, and I think it was so I could do 12 sheets in a jobo 3010 drum without exceeding the drum capacity.

[sanking]

Hmm, maybe I'll contact the Formulary and see what they think. I like the look of the Pyro Negs but a two stop speed drop is craziness.

You definitely should not see a two stop drop in speed with Pyrocat-MC, though there may be a slight loss in effective film speed compared to Xtol. Many of my tests also indicate that Pyrocat-HD gives just a tad more film speed than -MC, due to the phenidone, but the gain is quite small.

You should use at least 75 ml per sheet of 4X5 film, using the 1+1+100 dilution. My own tests for film speed were made with this dilution developing in BTZS tubes. With Jobo there is also a minimum amount that must be used depending on the drum. I don't use Jobo so don't know the total volume you need for your system, but more is always safer than less as it assures that all of the film is completely wet out during the first few seconds of agitation.

I would suggest increasing time of development by about 25-50%, and using more total solution. If this does not solve the problem, try the 2+2+100 dilution, there will be very little difference acutance compared to 1+1+100, but a fairly big bump in CI for the same time of development.

Sandy

[Kirk Gittings]

Sandy, On a side note....
As my BTZS 4x5 cap only holds 60ml of solution rather than 75ml, I use a dilution of 1.25:1.25:100. My math suggests this provides the same amount chemical activity and does result in proper highlight densities for my purposes.

[agregov]

I've found the 1:1:100 dilution requires a lot of chemistry to prevent early exhaustion. Currently, my development times for Pyrocat HD using TRX 320 in a Jobo CPP3/Expert 3010 (full 10 sheets) is 1000ml at 14 minutes to get 100asa (slow rotation setting on the processor). I also use XTOL and the same film TRX 320 can develop with 500ml (stock solution) at 8 minutes to get 400asa. I have just started working with TRX 8x10 and will be doing contact printing on Lodima (silver chloride paper) and have tested the 2:2:100 dilution. The negs look beautiful however I'm still at 100asa using the CPP3/3005 drum with 5 8x10 sheets. Worth noting, I was able to get good densities with 1000ml processing for 9 minutes in a full 3005 drum. So, as Sandy suggests, the 2:2:100 dilution is much stronger. If you go that route, you'll have to watch your densities. My 2:2:100 negs are much thicker (which is needed for contact printing with Lodima) but could be problematic for silver printing. Sandy may have some more thoughts on working with 2:2:100 for normal silver negs (which I'd be all ears as well)!

On a related note, I just started testing Rollei IR 400 film using Pyrocat HD and I'm having trouble getting that film to respond even at 100asa with the 1:1:100 dilution. Still more testing to do with Rollei but everything you are experiencing with 1:1:100 on a Jobo mirrors what I have seen with TRX (and now Rollei IR).

[Christopher Barrett]

Thanks, Everyone! Andrej, I'm also using the CPP3 with 3005 and 3010 drums. I'm now testing 4x5's with 100ml per sheet of 1:1:100 and going for 13 minutes this time. I believe that I was previously at 100ml per sheet with 4x5 and 200ml per 8x10.

Will report back.

[sanking]

Kirk,

You math sounds right to me.

I am pretty sure that Phil Davis used 60 ml of solution for all of his BTZS testing, but when I developed the Pyrocat formula I was using a set of home-made BTZS type tubes (made from ABS plastic) and the caps that held more solution than the commercial tubes, so I just filled them to the most convenient point for me and that amounted to about 75 ml.

Sandy



Sandy, On a side note....
As my BTZS 4x5 cap only holds 60ml of solution rather than 75ml, I use a dilution of 1.25:1.25:100. My math suggests this provides the same amount chemical activity and does result in proper highlight densities for my purposes.

[Christopher Barrett]

Jut souped a batch of 4, same image with ISOs from 100 to 32. With the increased solution quantity (200ml per 4x5) and 13 minutes of 1:1:100, ISO 64 is looking pretty good. Will continue to fine tune from here...

[Kirk Gittings]

Kirk,

You math sounds right to me.

I am pretty sure that Phil Davis used 60 ml of solution for all of his BTZS testing, but when I developed the Pyrocat formula I was using a set of home-made BTZS type tubes (made from ABS plastic) and the caps that held more solution than the commercial tubes, so I just filled them to the most convenient point for me and that amounted to about 75 ml.

Sandy

Thanks. When I started using PCHD at the normal 1:1:100 in the 60ml cap, I found I had a hard time reaching a proper highlight density no matter how long I developed (though I could get a decent scan anyway). That seemed to indicate to me that the developer was becoming exhausted. Then I read something you wrote about needing 75mls of the 1:1:100 dilution for a 4x5 sheet and realized it most likely was exhaustion and hence my solution. Works a charm now.

[John Layton]

I've been using Pyrocat HD for a few years now and love it. I also know that those pyrocat negatives which usually print most effectively tend to look somewhat thinner than my non-staining developed films. In fact it took some time for me to get used to this...that the slight stain can read as a bit more density than you might assume. Additionally, your densitometer might be a bit thrown off by the stain...although in your case it does sound like things are indeed too thin - but maybe ask Sandy about this. I also think that Kirk's "proper highlight densities for my purposes" makes a great point - that each of us has our own needs, and Pyrocat, thankfully, has been so very capable of adjusting its personality to suit our various goals.

[Kirk Gittings]

I've been using Pyrocat HD for a few years now and love it. I also know that those pyrocat negatives which usually print most effectively tend to look somewhat thinner than my non-staining developed films. In fact it took some time for me to get used to this...that the slight stain can read as a bit more density than you might assume. Additionally, your densitometer might be a bit thrown off by the stain...although in your case it does sound like things are indeed too thin - but maybe ask Sandy about this. I also think that Kirk's "proper highlight densities for my purposes" makes a great point - that each of us has our own needs, and Pyrocat, thankfully, has been so very capable of adjusting its personality to suit our various goals.

what he said.

[Alan9940]

IAdditionally, your densitometer might be a bit thrown off by the stain...although in your case it does sound like things are indeed too thin - but maybe ask Sandy about this.

FWIW, if you zero out the densitometer with a dark blue gel filter (I think it's a Kodak #42), then read densities through the gel you'll get readings pretty close to a non-stained negative. I got this tip directly from Sandy. Not sure exactly what it does--I think it simulates a stained negatives response to enlarging paper--but I've been working this way for about 8 months and the method seems spot on.

[Kirk Gittings]

FWIW, if you zero out the densitometer with a dark blue gel filter (I think it's a Kodak #42), then read densities through the gel you'll get readings pretty close to a non-stained negative. I got this tip directly from Sandy. Not sure exactly what it does--I think it simulates a stained negatives response to enlarging paper--but I've been working this way for about 8 months and the method seems spot on.

Interesting.

[Doremus Scudder]

FWIW, if you zero out the densitometer with a dark blue gel filter (I think it's a Kodak #42), then read densities through the gel you'll get readings pretty close to a non-stained negative. I got this tip directly from Sandy. Not sure exactly what it does--I think it simulates a stained negatives response to enlarging paper--but I've been working this way for about 8 months and the method seems spot on.

What this does is adjust the reading to the response of graded (blue-sensitive only) paper. VC paper is another can of worms, since it is sensitive to a broader spectrum from green to blue, and the exact mix of the two determines print contrast. It might be interesting to zero-calibrate the densitometer to a #2 or #2.5 Multicontrast filter and see what the results are.

Making a "proper proof" on the enlarging paper you are using is a pretty foolproof way to judge film speed and development time for stained negatives. The results aren't quantified (no density numbers) and it takes a bit of finesse to decide what degree of black one wants to use for "maximum paper black" in the proof, but once that has been decided, the results are obvious. I visually calibrate everything this way.

Best,

Doremus

[Rick A]

I think you have grossly underdeveloped your film. You probably need to be running around 18-19 minutes at 20c.

[Christopher Barrett]

Crazy thing is, the instructions that came with the developer called for 7:15 devel time. That didn't make sense to me, so I did some Googling and came up with 10 as a starting point. I think once I finally nail this down, I'll have to do another comparison with XTol to see if Pyro is really worth the effort.

[Alan9940]

What this does is adjust the reading to the response of graded (blue-sensitive only) paper. VC paper is another can of worms, since it is sensitive to a broader spectrum from green to blue, and the exact mix of the two determines print contrast.

All my enlarged PCat negatives are printed on VC papers--primarily Ilford MGWT and Fomabrom Variant 111--and most of my 8x10 negatives are contact printed on Lodima or Adox Lupex. I've been calibrating my PCat negatives with my densitometer for nearly a year using the dark blue filter and I've not noticed any anomalies when printing VC or graded. But, it is the way I work and others' results may be different.

[esearing]

Crazy thing is, the instructions that came with the developer called for 7:15 devel time.

7:15 is likely for a rotary processor with continuous agitation. 10 mins might be adequate for 1:1:100 with frequent agitation (1 minute intervals).
2 minute intervals add another 20%, 3 minute intervals add more time.

[sanking]

I created the PyrocatHD and variations formulas but have no control over development times put out by others. The only times I have tested, and control, are those described in the original article I published on PyrocatHD in the article at http://unblinkingeye.com/Articles/PCat/pcat.html, some 13-15 years ago.

In the original article, now on my website, I provided development times for rotary testing with BTZS type tubes for a number of films available at that time. The development times recommended were CI charts showing time of development, at a given dilution, for development to a specific CI. I have also provided details about developing film in Pyrocat with minimal agitation and with two-bath development in threads on APUG and on the LF forum, including an article on two-bath development on the Pyrocat web site, http://www.pyrocat-hd.com. Developing film in such a way that optimizes the nature of the film, developer, and method of printing, is obviously a rather high art that requires much investment of personal time, well beyond film development charts, however well they are done.

The original Pyrocat formula was originally published back in 1998 is in the public domain and I do not personally derive any profit from it. That said, I always attempt to provide useful information for persons who contact me in person about use of Pyrocat and its variations, and I often share information on this forum.

Xtol is a great developer, but at some point of magnification all pyro hardening and staining developers, including PMK and Pyrocat, are capable of higher resolution and acutance, though not all people use equipment or print or scan with equipment capable of showing the difference. Xtol does, however, give slightly greater effective film speed.

Sandy

[David Schaller]

Sandy,

I may have said this before, but if so let me say again, you have my deepest appreciation for your development of Pyrocat HD, and for your many contributions here on the use of it!

I have been using Pyrocat HD almost exclusively for many years as a result, for all formats, but it is especially useful for large format negatives, which I am able to print in both traditional silver or Pt/Pd.
My developing procedures are very simple, using hand inversion or tray development, and the developer is flexible enough to enable large N minuses consistently and predictably.

Thank you again,

Dave

[Andrew O'Neill]

Sandy,

I may have said this before, but if so let me say again, you have my deepest appreciation for your development of Pyrocat HD, and for your many contributions here on the use of it!

I have been using Pyrocat HD almost exclusively for many years as a result, for all formats, but it is especially useful for large format negatives, which I am able to print in both traditional silver or Pt/Pd.
My developing procedures are very simple, using hand inversion or tray development, and the developer is flexible enough to enable large N minuses consistently and predictably.

Thank you again,

Dave


What he said!