clay said:BTW, I ran one test at 1:1:200 for an hour. Still no elevated b+f. I like it.
sanking said:Clay,
I missed this earlier. What film was this? And what was the type of agitation? Tank with agitation every minute or so or rotary?
Sandy
Lukas Werth said:I just came across this thread, and I hate to admit it, but I have no idea about these to versions of Pyrocat; I only know Pyrocat HD. Running a search, have not found information on the net. Sorry to ask this basic question, but could anybody bring me up to date?
Maybe one other question: my working solution of pyrocat always becomes a bit cloudy immediately after mixing. Is this only me who experiences it, or also other? Can it be prevented?
Amund said:Sandy, am I right to think that I`ll get increased sharpness with with tray processing too?
When I have a lot of negs to develop, doing one or two in a rotary processor is tiresome, and I prefer to do 6-8 negs in a tray instead...
Lukas Werth said:The cloudiness occurs in the -working- solution, a second or so after adding the water to the stock solutions which I pour in first. It occurs with higher dilutions also. I have never noted anything special with my tap water here, it tests neutral, but seems to be very slightly alkaloid, which is why I use, where considered nececessary, a little bit citric for the first rinse.
I never tried to use destilled water for the working solution.
Tom Hoskinson said:Yesterday, I mixed a liter of Pyrocat P stock solution A in Propylene Glycol at 140F. I used a magnetic stirring hotplate and encountered no mixing difficulties. Following Sandy's suggestion, I left the KI out.
I developed a 120 roll of Fomapan 200T with the new "stock A" this morning, I used deionized water and the 1:1:100 Pyrocat dilution. When I mixed in the KCO3 "B" solution, the working developer turned a "Medium" blue. I developed Semi-Stand for 16 minutes at 71F, and the negatives (mostly Santa Monica Mountain landscapes) look great.
sanking said:Tom,
That is great to hear. I assume you must like the stuff if you mixed a whole liter. Did you get good stain with your mixture?
So the color of the working solution is blue? Very interesting. I am sure looking forward to hearing what color others get when they start to mix up their own. But another mystery. But whether blue or purple/lavender I like the idea of color as an indicator that both A and B solutions were used in the working.
Also, I am very interested to know if you see any difference in either B+F or sharpness with the potssium iodide left out? I did not see any difference with FP4+, but films are really very different so I am very curious about this.
Specifically about the B+F, I am speculating that the fact that Pyrocat-P appears to develop even less B+F stain with UV reading than Pyrocat-HD (which is no slouch at all in this regad) is due to the fact that the working pH is more in equilibrium since the threshold of pH for developer activity of pyrocatechin and p-amonophenol is much closer than pyrocatechin and phenidone. For silver printers the issue of B+F would not be much of an issue, but it might be for persons using UV sensitive processes. So for this reason the quesiton of the need for a restrainer remains in the air for me at this time.
Anyway, I really appreciate the feedback from those who voluntered to test the new formula.
Sandy
Tom Hoskinson said:Yes Sandy, the stain was very good - brown colored stain with good blue channel density. A dense highlight area measured 2.53 blue versus 2.03 visual.
B+F was .13 in both the visual channel and blue channel.
I have not put these negs under the microscope yet, but by naked eyeball, the sharpness is high.
lee said:Just a quick checkin Sandy. I did 2 4x5 FP4 at 1+5+500 @ 68F for 9 mins today and the pyrocat P was indeed purple. It was about the same color of the prewash.Seemed to get darker as it sat waiting for the prewash to take place. The film looks excellent. The color seemed a bit brown purple at the end. I am a happy camper and you should be too.
lee\c
Tom Hoskinson said:Sandy, the densitometer readings I took from my Efke 100 negatives developed for 16 minutes with stand agitation at 72F with the 1:1:100 dilution were: Visual Channel 1.47 and Blue Channel 1.65.
This Efke 100 was 35mm film developed with Pyrocat P "A" mixed in distilled water (not glycol) this "A" solution contained Potassium Iodide.
Tom Hoskinson said:Sandy, B+F was .23 for this roll of film.
Efke KB100 (35mm) listed substrate thickness is 125 micro meters. I verified this by measurement on the subject roll of film.
Efke PL 100 sheet film's listed substrate thickness is 175 micro meters.
sanking said:Hi Lee,
Thanks for the report. If you decide to mix up your own stock solutions of Pyrocat-P I am very curious to learn what color you get when mixing the working solution.
Best,
Sandy
Silverpixels5 said:I mixed up the Pyrocat-P(in glycol) for use with FP4+. Solution color went from light lavender to deep purple with time. Also, the FB+F ranged from 0.07 to 0.09 in the visual channel, depending on how long dev time was. This was with fresh FP4+ sheet film(4x5). Any similar results, or are my numbers out of wack? I should also mention that I was out of metabisulfite so I had to sub bisulfite. I will be making a batch with the metabisulfite next week when it arrives
Bruce (Camclicker) said:Is the p-Aminophenol used in Pyrocat-P known as Para-Aminophenol Hydrochloride or Para-Aminophenol Sulfate (Metol)?
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