Pyrocat HD Kit Impossible to Reconstitute?

[sanking]

"Second question regarding the Pyrocat Solution B (Potassium Carbonate), mine has quickly come out of "solution" and seperated into components. Is it normally a suspension like this, or is it suppose to stayed dissolved in the H20?"

Andre,

No, that is not normal. Once the potassium carbonate is dissolved in water it should stay in solution at normal room temperature indefinitely. I have 75% Stock B solutions on hand that are several years old.

However, I think your working solution will give good results so long as you shake vigorously the B solution before adding it to the working solution.

[Andre Noble]

Sandy, thanks for that input. Will shake before use, and also be more careful mixing it in first place (originally, I added the water to a 100ml volumetric flask full of it - took 1 hour to sort that mess out. Duh!!)

PS, Mike is right it's available here also:

http://bostick-sullivan.com/commerce/aa_41.htm

[John D Gerndt]

Andre'

I too have problems with the Photographer's Formulary kit solution B. I just double the dilution and then double the B volume in my use. As to the tiny 0.2 grams of Phenione, I wish it would come in a pellet, but rinsing out the bag IS a good idea.

Cheers,

[Mark_3632]

My solution B seperated too. Sounds like it is a common problem. I am glad to hear that shaking it before use is alright.

[sanking]

The Pyrocat-HD formula calls for a Stock B solution that is a 75% solution of potassium carbonate. That is what you get if you mix 100 g of potassium carbonate in 100 ml of water (makes a total of about 130 ml), or if you mix 75 g of potassium carbonate in water to make a total of 100 ml of Stock B.

I am not absolutley sure why the Formulary kit does not mix well. I suspect it is because the packet contains 100g of potassium carboinate and the directions say mix this in water to make 100 ml of Stock B. If so this makes a 100% stock solution, quite a bit stronger than my formula. I sent a message to Bud at Formulary about the issue but don't know if he has corrected the problem. In any event, the solution is to just add about 30 ml more of water to the Stock B solution to make a total of about 130 ml of Stock B.

[Andre Noble]

Sandy,

FYI, The Formulary Instructions read:

Part A: "Water to make 100ml"

Part B: "Water to make 100ml"

Thanks for the tip on the part B.

[E. U. Eichhorn]

Sandy,

The times you have at unblinkingeye.com are for the 75% solution, correct? Someone above says something about increasing development by 15% if using the 75% solution, which seems wrong if the times you have given are for the 75% solution.

However, I did do a roll of FP4+ 135 with EI of 100 in pyrocat-hd at 1:1:100 for 8 minutes @ 70degrees for non-UV printing and the negs came out pretty thin. These were developed using an earlier batch of Pyrocat-HD from PF that had the 100% solution B. So, maybe you must increase 15% development time when using the 100% solution B?

I just mixed a 500ml kit last night I received from PF. The instructions did have the B solution at 100%. I increased the amount of water to make it 75% and mixed by adding very very s l o w l y and it completely dissolved with no precipitation problems after sitting all night.

Thanks,

[Frank Lahorgue]

Oops -- I should have been more clear. I added 15% to my own times when switching from PF to the B&S kit, not to Sandy's. I was indeed trying to use a 100% solution B by following the PF instructions.

[sanking]

All of the recommended development times I have provided are based on the use of a 75% Stock B Solution of potasssium carbonate. I may have suggested at some point that one might need to reduce development times a slight amount if using the Formulary kit, and minus10-15% is about what I would try, but bear in mind that I have never actually worked with the kit so this is just a ball-park suggestion.

The most recent tests I did with Ilford FP4+ and Pyrocat-HD, 1:1:100 dilution, indicate that a development time of about seven minutes at 72 degree F, with rotary processing, should give enough contrast for printing on a #2 silver paper, with subjects of normal contrast. You would probably need to increase times slightly for VC papers by about two minutes. And if you are using other than constant agitation this needs to be factored in as well.

Thin negatives can result from both under-exposure as well as under-development, but the former is by far more common than the later in my experience.

[Andre Noble]

Regarding thin FP4+ Negs, I agree, probably due to underexposure. I would try rating the FP4+ in Pyrocat HD at ASA 40.

I have not used Pyrocat but FP4+ in Pyrocat HD and FP4+ in Wimberly WD2D+ (which I do have experience with) are supposedly similar.

I found the true film speed of FP4+ in WD2D+ Pyro is ASA 40 despite claims that WD2D+ delivers true film speed.

Yes, every film manufacturer and developer manufacturer likes to rate B&W film speeds too high. This serves their marketing strategy (they think), but they don't calculate the loss of a customer who quits using their product early because they are not getting technically successful results.