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_tf_
14-Oct-2021, 12:00
I mixed my first batch of Pyrocat HD yesterday, using the powder kit from Photographers Formulary. The contents of the bag for the B solution were not homogeneous, it contained pure white crystals, but there were also some roundish granules near the top, dirty yellow , I assumed maybe there was a bit of moisture in the bag that caused this. But when I mixed the solution it went muddy green. From my googling around today, it would seem solution B is meant to be clear. I did use the same mixing glass beaker as for A, but I did wash it really thoroughly between A and B; perhaps not thoroughly enough. My question is whether if this is caused by contamination with A it makes B unusable? I was looking forward to trying it out at the weekend, but it will be at least a week before I can get my hands on some potassium carbonate to mix a fresh solution B.

Jim Noel
14-Oct-2021, 13:28
If you have access to an unexposed roll of 35mm here is a possible answer to your question.
1. Clip off a small piece the exposed end of the 35 mm film.
2. mix about 2 or 3 ml of A with a similar amount of B
3. with the lights on, put the film in a small container and pour the developer on it. swirl it around to agitate.
4. after 3-5 minutes the film should begin to darken. If so, your B is good.
By the way, i expect it to be good.

Greg Y
14-Oct-2021, 13:54
_tf_ I've used Pyrocat for many years, but always from liquid, first from the original formula, then the Formulary version in glycol. As a habit, I never use the same container for A & B..... & i think this would be even more important when mixing the stock from powder form. The risk of contamination is IMO too high. Then when work from the stock, I use 10ml graduated cylinders rather than pipettes....& i have them marked A & B....& never use them for any other purpose. Good luck with your tests.

esearing
15-Oct-2021, 04:21
Green is bad - You can try Jim's test but even if it works once or twice it will fail eventually.
You can use plain old washing soda (Sodium Carbonate) but use it at ratio 1A + 2.5B Stock +100W of working developer. The working solution should be clear to light pinkish tan and must be used immediately upon mixing.
Time/temp should be same but I usually give it an extra 30seconds of agitation near the beginning.

Stock B washing soda
Distilled Water 700ml
Sodium carbonate 200g
Distilled Water to 1 liter

Or mix it fresh 5G per liter of distilled water for a working solution. If the washing soda has been open a while use 6g maybe 7g. For use in a 500ml tank: Start with 500ml working B and add 5ml part A.

_tf_
15-Oct-2021, 09:46
Thank you everyone. Interestingly enough when I drew it out of the bottle today to use it was almost clear, just little pink hue but very faint, and the developer worked, negatives came out stained brown, will get a better idea once they are dried. But I’ll replace the B solution as soon as the potash arrives. I am fairly certain the culprit was the plastic stirrer, will use different ones for each solution, and glass ones, in the future.

paulbarden
15-Oct-2021, 12:39
I made up a 500ml batch of this 2 weeks ago, and like you, I found the Potassium carbonate looked dirty in the package and the solution ended up a greenish-brown color. I've used it several times since and it works just fine. I did filter out the sediment that formed though.

_tf_
15-Oct-2021, 13:40
I made up a 500ml batch of this 2 weeks ago, and like you, I found the Potassium carbonate looked dirty in the package and the solution ended up a greenish-brown color. I've used it several times since and it works just fine. I did filter out the sediment that formed though.

Ah, I wonder if there is sediment on the bottom of the bottle, I used a syringe so wouldn’t have stirred it getting it out.

_tf_
16-Oct-2021, 07:00
This is Fomapan 100, developed for 11min, agitation for the first minute, then 10s on the minute (dodged the upper river a bit in C1); I think I'll cut down the initial agitation a bit, it's little bit too contrasty for my taste, but all in all I like the look and the tonality, this might well become my go to developer instead of Excel(Xtol).

https://live.staticflickr.com/65535/51595534148_c54c49c790_b.jpg (https://flic.kr/p/2mBjAJY)Riverside (https://flic.kr/p/2mBjAJY) by tthef (https://www.flickr.com/photos/_tf_/), on Flickr

Daniel Unkefer
16-Oct-2021, 07:09
Wow that looks really good ^^^ :) Nice job

Greg Y
16-Oct-2021, 08:04
tf, Pyrocat is indeed a fine developer. I've used it as my standard for over a decade now. With rollfilm, I agitate (gently) for the first 30 sec then 10 sec/min....though with just one photo to go from it's hard to say what relates to the scene contrast & exposure. I particularly like the highlight separation with pyro developers. Glad to see your B solution worked out.

koraks
16-Oct-2021, 22:31
Thank you everyone. Interestingly enough when I drew it out of the bottle today to use it was almost clear, just little pink hue but very faint
Yeah, sounds like you had a drop of A carry over into B when you mixed it. It's not a big problem. Carry over of B into A would have been a problem; the other way around isn't very problematic.
What it does show is that what you considered a thorough wash of a container actually wasn't entirely thorough enough.