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Kirk Gittings
17-Jan-2015, 15:12
Just checking in with other's experience here. I tend to develop film once a year-usually over an intense two week period. I bought the large size from PF last year and developed a lot of film in February-first time I had any amount left over worth saving. When I was caught up I added very clean marbles to reduce air exposure, put the cap on tight and stuck the bottles in my darkroom fridge. I got the PC out yesterday, shot some test negatives and did a run, the developer is dead as a doornail. I half expected this and that is why I ran test shots. I'm not complaining. The stuff is very economical and I had used most of the bottle.

Would that be typical shelf life exhaustion in your experience? Could I have done anything else to preserve it better? One of these days I'll get into mixing my own but for right now what do you think about off the shelf shelf life of this and my methods?

Peter De Smidt
17-Jan-2015, 16:01
My bottles are a number of years old, and they're still going strong. No marbles. No fridge.

Kirk Gittings
17-Jan-2015, 16:08
I'm curious then what I did wrong. Any ideas? I use separate pipettes for the A&B solutions-virtually no chance for cross contamination.

Peter De Smidt
17-Jan-2015, 16:28
Are you shaking the B solution before using? I do. Contamination would usually be the most likely reason for early developer failure, but in your case that's unlikely.
I'm using the Pyrocat-MC in glycol. Maybe it has a better shelf life?

BarryS
17-Jan-2015, 17:43
I've used three year old Pyrocat-HD in glycol from PF and it worked perfectly. I mix my own now and compared freshly-mixed with the dregs of PF Pyrocat--the negative density was exactly the same--no loss of activity. I use two dedicated pipettes for aliquoting, and have noticed it can be hard to rinse out the part A due to the viscosity of the glycol. No marbles, no fridge, my developer is stored on a darkroom shelf.

domaz
17-Jan-2015, 22:12
My experience with Pyrocat in Glycol from the Formulary is the same as yours Kirk. After 9-10 months it just dies with little warning. My new policy is after 6 months throw it out.

Keith Fleming
18-Jan-2015, 11:45
Despite my doubts, could the refrigeration be the culprit? That seems to be difference in these posts.

Keith

Richard Wasserman
18-Jan-2015, 12:44
It does seem odd Kirk. Do you have any idea when PF mixed it? Maybe it already had some age when you received it. I mix Pyrocat in water and it lasts at least as long as yours in Glycol has, I don't do anything special, no marbles, etc. Maybe it is time to mix your own? It's easy to do and guarantees having fresh chemicals.

IanG
18-Jan-2015, 12:54
I make up my own Pyrocat HC in water, I've some that'll be 4 years old in March and it's still fine. You must use glass or high density plastic bottles for storage, also fresh Metabisulphite as it gives off SO2 which prevents the Pyrocatechin from oxidising.

In Turkey I have some double strength Part A in Glycol that's still fine after about 5 or 6 years, I made it double straighten to cut the weight flying with it.

Someone commented on one of the forums that the PF bottles weren't good enough, even with Glycol there has to be a small amount of water to dissolve the metabisulphite. I made this mistake once using some smallish lower grade plastic bottle and the Pyrocat (water only) wasn't lasing a month. Low grade plastic bottles allow oxygen to diffuse through the wall into the solution.

Ian

Kirk Gittings
18-Jan-2015, 12:58
I have been storing the PF PC in the brown plastic bottles they came in. Maybe that is it?

Alan Curtis
18-Jan-2015, 13:05
Kirk
My experience is just like yours. PF PC in the original bottles and in one year dead. I now use brown glass bottles, I'm over a year now and all seems good.

David Karp
18-Jan-2015, 13:06
I had some Pyrocat MC in glycol from the Formulary that went bad in perhaps one year. In fact, it sat unopened in the original bottles for that time. I think that supports Ian's theory.

Taija71A
18-Jan-2015, 13:10
I have been storing the PF PC in the brown plastic bottles they came in. Maybe that is it?

__

Perhaps...

As per Ian's comment... 'Low grade plastic bottles (definitely) allow oxygen to diffuse through the wall into the solution'.

Thus, my suggestion to you yesterday... That Amber/Brown Glass Bottles are always best!
--
Best regards,

-Tim.
_________

sanking
18-Jan-2015, 13:10
...
Someone commented on one of the forums that the PF bottles weren't good enough, even with Glycol there has to be a small amount of water to dissolve the metabisulphite. I made this mistake once using some smallish lower grade plastic bottle and the Pyrocat (water only) wasn't lasing a month. Low grade plastic bottles allow oxygen to diffuse through the wall into the solution.

Ian

I believe Ian has identified the problem. There is in fact a small amount of water in the Pyrocat in Glycol solutions sold by the Formulary as it is needed to get the bromide and metabisulfite in solution at a fairly low mixing temperature. But if oxygen diffuses through the wall of the plastic it can cause Solution A to go off. I always mix developers in glass, never plastic. If you buy any version of Pyrocat in plastic containers I recommend that you transfer it to glass as soon as possible.

At this time I mix a slightly different version for my own work that avoids any water at all, Pyrocat-HDC. In the HDC formula bromide and metabisulfite are replaced by ascorbic acid. Results with -HDC are virtually identical to the original Pyrocat-HD formula.

Pyrocat-HDC (Solution A mixed in glycol)
Stock A
Propylene Glycol at 150F 750ml
Pyrocatechin 50 g
Phenidone 2.5g
Ascorbic Acid 4.0g
Propylene Glycol to 1000ml

See http://www.pyrocat-hd.com/html/mixing.html for other mixing information.

Sandy

jp
18-Jan-2015, 13:37
Sandy; could HDC be made with water instead of propylene glycol to save an ingredient and a couple bucks? I don't need it to last forever.

sanking
18-Jan-2015, 13:42
Sandy; could HDC be made with water instead of propylene glycol to save an ingredient and a couple bucks? I don't need it to last forever.

Yes, you could mix -HDC in water. I just have no idea how long it would last. To save money you could actually mix -HDC in ethylene glycol (aka anti-freeze) rather than propylene glycol.

Sandy

Richard Wasserman
18-Jan-2015, 15:16
I store my Pyrocat in glass bottles. If the bottles are kept in a dark place, i.e. refrigerator, darkroom, etc clear is fine.


Kirk
My experience is just like yours. PF PC in the original bottles and in one year dead. I now use brown glass bottles, I'm over a year now and all seems good.

Kirk Gittings
18-Jan-2015, 15:29
Glass bottles....sounds like a plan.

Flauvius
18-Jan-2015, 15:52
Based upon my following experience in storing and using the PF's Pyrocat-MC, plastic bottles are not likely to be the problem. Allow my to explain:

I have developed developed Tri-X 320 over many years by use of the semi-stand method, and in a can. I have consistently used the 1:1:100 ratio that Sandy recommends, and my staring temperature is 71 degrees Fahrenheit as determined by a Kodak No. 2 thermometer. My Ambient temperatures range from 66-71 degrees Fahrenheit.

Shortly before X-Mas of 2011, I received a liter of Pyrocat-MC in a plastic bottle from the Formulary. As is my practice, on December 28, 2011 I decanted the Pyrocat into two 500mm Boston Amber glass bottles. in turn, I sealed the bottle tops with several layers of Surran wrap, and then taped the Surrran wrap to the bottles.

On January 11, 2013, I did the same thing with another shipment of Pyrocat-MC from the Formulary. Once open, I do not use marbles to displace oxygen from my bottles of either Parts A or B.

I have used Pyrocat-MC for several years and am I well aware of its "Sudden Death" characteristics/. Long ago discussed this issue with Sherry of the Formulary. Although Sherry has suggested "that a litte' amber is ok, my experience has been that even "clearish" Pyrocat that I have stored for a year can be dead, and without being subject to any possibility contamination.

As such, this afternoon I opened a "fresh" bottle of Pyrocat that I had stored since December 28, 2011 to develope a few negatives. Is was like Vermont syrup, dark amber. So, 500mm of Pyrocat MC went down the drain. Then I opened a bottle from my January 11, 2013 shipment. Wile it was not as "dark" as the bottle from December 28, 2011, it too was distinctly "brownish". So, another 500 mm of Pyrocat MC went down the drain. However, not to be denied I opened a bottle of the Pyrocat-MC that I received from the Formulary on December 16, 2014. Although it was slightly "yellowish", it performed as I expected.

Accordingly, based upon my years of using Pyrocat-MC, I have concluded:

1. Don't stock-up on Pyrocat-MC part A, it "goes bad" after 6 months.

2. If Part A is anything other than "slightly amber/brownish", it is likely to be bad.

3. Once the 500mm glass bottle is half empty, throw the remain down the drain. Since I use a syringe with a length of polypropylene to extract Part A, I suspect that with each extraction oxygen is introduced into the bottle and, which, starts to oxidize Part A. Indeed, I have had bottles that were half full, were only faintly "brownish", but produced nearly no development.

4. Part B does not change color and does not seem to subject to oxidation. In short, Part B does not seem to "go bad". Indeed, I have used Part B that was six years old with "fresh" Part A and the negatives developed nicely.

My only suggestion to forego Pyrocat-MC's sudden death problem is that Sandy introduce a true color indicator into Pyrocat-MC, but which does not impact upon the developer's ability to produce negatives of the type processed in fresh Pyrocat.

Flauvius
18-Jan-2015, 15:58
Kirk:

As for bottles for use with Pyrocat, I would suggest that you only use new bottles to avoid the possibility of residue contamination.

Flauvius

Kirk Gittings
18-Jan-2015, 16:07
Thanks. I just ordered some from Specialty Bottle.

sanking
18-Jan-2015, 19:19
The color of stock solutions of Pyrocat mixed in glycol varies quite a bit depending on whether it is -HD, -MC, or -P.

Pyrocat-HD Stock Solution A mixed in glycol or water should be clear, or very light amber. If the solution is brown it is virtually certain that it has gone bad.

Pyrocat-MC Stock Solution A mixed in glycol begin as light brown, and turn darker within one or two months. The color is not an indicator that the developer has gone bad. MC can be very, very brown (black coffee) and still have full energy.

Pyrocat-P Stock Solution A mixed in glycol begin as light pink, and turn gradually darker pink. The pinker color is not a certain indicator that the solution has gone bad.

All of the Pyrocat Stock solutions A mixed in glycol should keep their energy for up to a year. However, because the developer uses such a small amount of reducer (one of the primary reasons for its high acutance), and needs a fairly high pH for development, Pyrocat stock solutions are easily ruined by cross contamination, even of a minute amount.

Stock B for all Pyrocat formulas is a straight 75% solution of potassium carbonate. It should last for years in a glass bottle mixed in water.

Sandy

John Bowen
18-Jan-2015, 20:25
My pyrocat HD was mixed in propylene glycol in Nov 2010. I last developed negatives in Sep 2014 and my HD performed like a champ. I mix my own, all my chemicals came from Artcraft and I use Amber glass bottles to store the HD.
PS the bottles used in Sep were less than 1/2 full when I started and the last time I developed film before Sep was back in 2013. Given the cost of PG, I always wondered why the formulary didn't charge more for their PG version.......hmmmmmm

Peter De Smidt
18-Jan-2015, 21:36
My MC is in the original PF bottles. As Sandy says, it's pretty dark colored.

IanG
19-Jan-2015, 06:50
Personally I'm happy to mix the stock solutions of Pyrocat HD with water, I use de-ionised, knowing from experience Part A lasts well in good bottles. Under normal circumstance I'd be using it up reasonably fast, if I want or need to keep some for a long time I'd make it up in Glycol.

I learnt the hard way that using the wrong bottles brings rapid failure, I thought in small plastic bottles (150-200ml) I'd keep it fresher, instead I had to discard it all in under 3 months.

Ian

Peter Lewin
21-Jan-2015, 14:42
Great thread, especially since I am about to order a new batch of Pyrocat HD in Glycol from PF. I gather from the general commentary that the first thing I should do is transfer the two solutions from the PF-supplied plastic bottles to glass bottles. I happen to have one of those wine bottle pumps and a bunch of the related rubber stoppers, so would it be a good idea to use those instead of the usual bottle screw tops, and pump out the air each time I re-seal? Also, given the shipping costs from PF, and their own economies of scale, anything wrong with buying the 50-liter kit, which might last me two years, versus the smaller 10-liter kit which will obviously last me much less?

I only switched to Pyrocat HD a couple of months back, and have found that it avoids some of the unevenness I would occasionally get from PMK, but I was also used to PMK's very long shelf life.

Cor
22-Jan-2015, 02:42
A bit related; I have been using PyrocatHD for years, keeping it in glycol, glass bottles (clear ones, stored in the dark, so the colour can be judged0, never had it "drop dead"..only suddenly 2 years ago I suddenly got a white precipitate in stock A. Gently heating did not get the precipitate back into solution. Although the developer still performed as usual. The white precipitate is a mystery to me, I used the same chemicals and (clean) bottles as always.

Anyway Sandy advised me to switch to Pyrocat HDC: that solution stays clear and no precipitate (also it does not need extra water also), and I have been happy with it !

Best,

Cor

Ps: that 3 years old Pyrocat HD stock with precipitate still works perfect: I use it to re-develop bleached negative with it.

Kirk Gittings
24-Jan-2015, 15:34
I apologize to everyone on this thread. The problem referred to here was purely user error-a total brain fart. My year old developer is fine. It was just a stupid dilution error.

Richard Wasserman
24-Jan-2015, 15:36
I think that all of us here can sympathize with brain farts! I'm glad you solved your problem.


I apologize to everyone on this thread. The problem referred to here was purely user error-a total brain fart. My year old developer is fine. It was just a stupid dilution error.

Kirk Gittings
24-Jan-2015, 15:57
In any event there was some interesting points made. I will switch to amber bottles anyway, and keep using the marbles and think about HDC.

BTW what would you all say is the basic equipment I need to mix my own?

Richard Wasserman
24-Jan-2015, 16:20
Other than what you you already have—beakers, etc, you'll need a scale to measure small quantities of chemicals. I use an Ohaus digital scale, but there are many other options—I'm sure you could pick up an Ohaus triple beam fairly inexpensively. That's about it. It doesn't take much and it's not the least bit difficult.

David Karp
24-Jan-2015, 16:42
I picked up a digital jeweler's scale on eBay from a seller called Old Will Knot, or something like that. It came with a calibration weight. The scale works very well. I get some very small paper cups to spoon the chemicals into. Oh yeah, you need a spoon too. :-)

Richard Wasserman
24-Jan-2015, 16:56
One more thing—get a GOOD dust mask to wear when working with the Pyrocatechin. A high quality, not a flimsy one strap dust mask, particulate respirator that will protect you from very fine dust. That and good ventilation—Pyro is not something you want to be breathing.

NPR
24-Jan-2015, 17:16
If you are looking for a scale, I second one from Old Will Knot, spent about $30 and accurate. I use the little dixie cups to measure small amounts. I also have some formulary Pyrocat-HD from 2/2012 that is still going strong today. I did put the A sol. in glass before the end of the first year. I also use separate syringes marked for A and B. There is some sediment or something at the bottom of the A bottle , but it works like the first day. If you want to save money on glycol you can mix it yourself at 2x, but you can still get it at the Tractor Supply store for about 20 dollars a gallon and it's 99% pure. The best thing about -HDC and -PC is that all you have to do is measure out the chemicals, put them in a bottle and pour in the p. glycol, stir, wait, and then stir each day. I also have some home mixed pyrocat-mc with the metol and AA in 100ml of glycerine at 250F that is going strong after two years and it has not changed color; it is still a very light red/orange. As for air, I don't use marbles, but I do put the solution in a smaller bottle when I can. Pyrocat-PC is the one that seems to change color over time, I have some that looks black but it works just like it did when I mixed it.

HMG
24-Jan-2015, 22:27
I apologize to everyone on this thread. The problem referred to here was purely user error-a total brain fart. My year old developer is fine. It was just a stupid dilution error.

Well, I (and probably others) still learned something.

Kirk Gittings
25-Jan-2015, 13:58
Found an Ohaus triple beam here locally for $15. Am I going to need a set of calibration weights?

Richard Wasserman
25-Jan-2015, 14:06
PM me with your address and I'll be happy to send you one.


Found an Ohaus triple beam here locally for $15. Am I going to need a set of calibration weights?

Kirk Gittings
25-Jan-2015, 15:25
I emailed it Richard. Thanks so much!

Peter De Smidt
25-Jan-2015, 15:51
I'm relieved you figured it out. I did that once, as well. To minimize contamination chances, I use a syringe for part A and a very small graduated cylinder for part B.

Jim Shanesy
25-Jan-2015, 17:58
J

Would that be typical shelf life exhaustion in your experience? Could I have done anything else to preserve it better? One of these days I'll get into mixing my own but for right now what do you think about off the shelf shelf life of this and my methods?

I get mine pre-mixed from Bostick and Sullivan and keep it in the bottles they send it in at room temperature. It's perfectly fine for at least a year.

Cor
26-Jan-2015, 07:29
I find a magnetic, heated stirrer very handy:

http://www.keison.co.uk/stuart_cr302.shtml

This is a realy fancy one, but if you are patient and look at the usual places you must be able to find a cheaper (second hand) example.

Best,

Cor

Ed Richards
28-Jan-2015, 07:25
I would seriously weight the incremental benefit of mixing it yourself against the potential risks of introducing seriously toxic chemicals into your environment. I would at least mix it outdoors, rather than in the darkroom.

Kirk Gittings
28-Jan-2015, 08:04
Even though the OP of this thread was a false alarm, I'm interested in maximizing shelf life so there are no surprises-so the HDC version is especially attractive and it is not available commercially. So I would really be mixing it just once a year at most. Which of the ingredients are so toxic?

Richard Wasserman
28-Jan-2015, 08:52
Pyrocatechin is the one you need to worry about, especially in its powder form. You don't want to breathe it which should become obvious if you smell it—it's not pleasant. Not that I recommend that you stick your nose in it... Work neatly, wear a good particulate respirator, and have good ventilation—outdoors isn't a bad idea. Once it's mixed the breathing issue goes away. Wear Nitrile gloves if you're putting your hands in it, otherwise don't drink it or bathe in it and you'll be fine,

Jim Noel
28-Jan-2015, 09:05
Pyrocatechin is the one you need to worry about, especially in its powder form. You don't want to breathe it which should become obvious if you smell it—it's not pleasant. Not that I recommend that you stick your nose in it... Work neatly, wear a good particulate respirator, and have good ventilation—outdoors isn't a bad idea. Once it's mixed the breathing issue goes away. Wear Nitrile gloves if you're putting your hands in it, otherwise don't drink it or bathe in it and you'll be fine,

Pyrocatechin is certainly the most toxic in the formula, but the wearing of a dust mask and care in adding the powder to the liquid will prevent any problems. I have been mixing my own pyrocatechin and pyrogallol developers since the 1940's with no health problems resulting. Carefully dip the spoon in the powder and place it very low above the weighing paper so you don't cause the very light powder to become airborne. Do the same when moving the powder from the scale to the liquid.

By the way, many who warn against the use of these chemicals mix their own developers using hydroquinone which is at least as toxic.