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Re trying to get all the borax or other alkali
Re dissolving the needed amount of borax in glycol, I wonder if a bit of hydroxide could help. Gainer and others have said that adding a small amount of water to organic solvent developers does not ruin the shelf life. Some say 3 - 5 ml is okay. But when people raised safety concerns about working with hot solvents, Gainer said that one could entirely dissolve the developing agents in water and then add that to lower temperature solvent. To do that would seem to require more than 5 ml. of water. If one added a saturated solution of hydroxide in water when making 510B, could that allow one to reduce the borax or metaborate enough to get them to dissolve in the glycol? I guess the question is how much water can be added to glycol solutions before it ruins the shelf life?
@bluechromis do you know what the pH is of PG-110B when diluted 1+100 as recommended? It seems like a low amount of borax vs what I am using. It seems surprisingly low, actually. I would expect pH to be lower than PC-512 Borax and thus slow, but he says it's roughly D-76 times. Possibly made up for by double the phenidone concentration. Do you get normal contrast negatives and box speed?
My local grocery store carries a 55 oz box of ARM & HAMMER Super Washing Soda for $5.69, which is much cheaper than Amazon's prices. I'm glad I read this thread!
Haha, yeah, you would have found a suitcase full of random shopping: the expat suitcase loaded with all the (non-perishable) stuff that we miss from home.
Thanks for the info!In Jay Defehr's process of formulating PG110B, his first step was to make a version of PC-TEA called PC110, with ten grams of ascorbic acid and one gram of phenidone. This is much more phenidone than the original. Jay say he was not entirely satisfied with that because the pH was too high which fostered graininess and he didn't need such a high pH with the amount of developing agents he used. So then he switched to glycol as the solvent. This might have made it easier to dial in the amount of alkali. I know the TEA is problematic for some folks. Still, I have wondered if another way to solve the problem of PC110's excessive pH would be to substitute some of the TEA with glycol. Then you avoid the problem of having to dissolve a separate alkali component. It seems like such an obvious thing to do that I have assumed there must be something wrong with it or people would have done it long ago.
But I must say, there seems to be a recent surge in the number of people packing freshly killed chickens or freshly made sausages into their luggage!
Washing soda - no problem! No freshly killed chickens are permitted.
This is exactly what I expected. I think that PG-110 pH is perhaps too low! Opposite problem to PC-TEA.For some reason, I need considerably longer times with it than reported by Jay, i.e., like D-76. I don't know why it seems less active for me.
Regarding the idea of the having an ascorbate developer in two parts both mixed in water, with the alkali entirely separate, Gainer said there many be some challenges with that:
"The usual ploy of making an acidic stock with the developing agents and a separate stock with the alkali is not foolproof when ascorbic acid is one of the agents. It is an antioxidant even in acid solution. The ascorbic acid-phenidone solution will protect the phenidone from aerial oxidation at pH values below film developing activity, but after enough ascorbic acid has been converted to dehydroascorbic acid, you will have the "sudden death syndrome" because the activity of the phenidone-ascorbate developer depends on regenerating the phenidone.
At pH values below the activity point of ascorbate, a very much greater amount of ascorbic acid than the minimum required for superadditivity does not increase the developer activity. If a buffering alkali such as borax is used, you could wait til doomsday to see any activity from ascorbate alone. Add a very small amount of phenidone and the activity jumps. I have found that the storage life of a complete developer containing 0.04 grams of phenidone, 8 to 10 grams of ascorbic acid and 24 grams or so of borax in a liter of developer is quite good. The working capacity is also quite good, so that several rolls may be developed in a liter of solution, either all at once or in succession."
"Incidentally, if you want to make a two solution developer, make the first solution with 0.8 grams of phenidone, 2 teaspoons of ascorbic acid powder and 2 tablespoons of borax in a liter. Make the second solution 2 teaspoons of ascorbic acid and 2 tablespoons of borax in a liter of water. Experiment to find the proportions of the two solutions that give you the development time and contrast you want."
https://www.photrio.com/forum/threa...pers-for-longer-shelf-life.30377/#post-427437
Arm & Hammer™ Super Washing Soda = sodium carbonate?
Wow, people are… amazing. I promise that I never once considered packing a freshly killed chicken in a suitcase. Or even a frozen one
Karl,
You've never had chicken until you have had one that has been wrapped in jockey short & socks, then marinated in a nice warm suitcase. Makes my mouth water just thinking about it!
What is the common or brand name for sodium carbonate at the grocery store? I need to buy another batch for D-72.
Probably Andy is broadcasting signals.Clearly, option 2 is more likely. The weird, and potentially scary part of it is, my memory may be going. Well, maybe not just yet, but that was a weird experience. Possibly the weirdest yet with regard to photography.
my memory may be going. Well, maybe not just yet, but that was a weird experience.
Another conspiracy theory bites the dust; life becomes even duller.Contrary to other comments, there's no war on washing soda; if it's gone from supermarket shelves, it's due to slow sales, not any sort of ban.
Test 1
I was thinking last night about @albada saying a few times that I should try metaborate in glycol. Referring to the solubility numbers I could find, it doesn't really pencil out as mentioned a few posts back. But I found some numbers for borax that showed that solubility might actually be higher in glycol than in water and I thought that might be even more true for metaborate. And then I was thinking last night that the solution will of course not be only glycol and metaborate: it will also contain ascorbic acid and phenidone. And actually that amount of acid could substantially change the solubility of sodium metaborate. So thanks to Mark (@albada) for mentioning it again. I did an experiment this morning (day off) and was able to get about a 50% solution of metaborate in glycol once the ascorbic acid was added. I tested the following:
This translates to a full formula of (DO NOT USE):
- 6ml of propylene glycol
- 3g sodium metaborate
- 0.7g ascorbic acid
- 0.03g phenidone (from 2.5% glycol solution)
- Stirred and heated into solution
This turns out to actually be too much metaborate and the resulting pH is too high at about 9.25. Knowing this was too high, but wondering what effect that would have on times and density, I tested with a small strip of Ilford Delta 100 and backed the time down to 6 mins 15 secs at 20C. Resulting clip density was way too high at about 2.5 and those are unusable dev times for other films (e.g. Fomapan would be like 4 mins).
- 100ml propylene glycol
- 50g sodium metaborate
- 11.67g ascorbic acid (target is 12)
- 0.5g phenidone
But it looks like there is a possible route there to a working developer.
Test 2
I did a further test to try to narrow in on the amount of metaborate needed to match the pH. I took 6ml of the PC-512 developing agents and added to 300ml of water. I then added small amounts of sodium metaborate and measured pH until I got to about 8.4. This is close to the borax version. I then tested a leader of Ilford Delta 100 for 6 mins 40s at 20C, the time I would normally use. I got a density of 2.10, which is just slightly under what I would normally get. I then developed a full roll in:
Since the density was slightly low, I ran the short film clip for 7 mins. Results look pretty good. Eyeballing it I would say base + fog is a little higher, and maybe density a bit lower. Will post better numbers when the film is dried and I can measure it and scan it.
- 300ml water @ 20C
- 6ml PC-512 concentrate
- 1.2g sodium metaborate
View attachment 332382
The idea then would be to try to make a single concentrate with that amount of metaborate. Assuming that it doesn't change its pH substantially when combining with glycol in solution.
Another conspiracy theory bites the dust; life becomes even duller.
Thanks for the info!
I had the same thought regarding TEA and glycol mixed and it would work, but you still don’t have a very good buffer that way. This is why earlier on the thread I started testing out a version that has just enough borax to dissolve in glycol and added TEA for the remaining alkali. I will try to get back to that tomorrow as I have the day off. That might be one path.
Test 1
I was thinking last night about @albada saying a few times that I should try metaborate in glycol. Referring to the solubility numbers I could find, it doesn't really pencil out as mentioned a few posts back. But I found some numbers for borax that showed that solubility might actually be higher in glycol than in water and I thought that might be even more true for metaborate. And then I was thinking last night that the solution will of course not be only glycol and metaborate: it will also contain ascorbic acid and phenidone. And actually that amount of acid could substantially change the solubility of sodium metaborate. So thanks to Mark (@albada) for mentioning it again. I did an experiment this morning (day off) and was able to get about a 50% solution of metaborate in glycol once the ascorbic acid was added. I tested the following:
This translates to a full formula of (DO NOT USE):
- 6ml of propylene glycol
- 3g sodium metaborate
- 0.7g ascorbic acid
- 0.03g phenidone (from 2.5% glycol solution)
- Stirred and heated into solution
This turns out to actually be too much metaborate and the resulting pH is too high at about 9.25. Knowing this was too high, but wondering what effect that would have on times and density, I tested with a small strip of Ilford Delta 100 and backed the time down to 6 mins 15 secs at 20C. Resulting clip density was way too high at about 2.5 and those are unusable dev times for other films (e.g. Fomapan would be like 4 mins).
- 100ml propylene glycol
- 50g sodium metaborate
- 11.67g ascorbic acid (target is 12)
- 0.5g phenidone
But it looks like there is a possible route there to a working developer.
Test 2
I did a further test to try to narrow in on the amount of metaborate needed to match the pH. I took 6ml of the PC-512 developing agents and added to 300ml of water. I then added small amounts of sodium metaborate and measured pH until I got to about 8.4. This is close to the borax version. I then tested a leader of Ilford Delta 100 for 6 mins 40s at 20C, the time I would normally use. I got a density of 2.10, which is just slightly under what I would normally get. I then developed a full roll in:
Since the density was slightly low, I ran the short film clip for 7 mins. Results look pretty good. Eyeballing it I would say base + fog is a little higher, and maybe density a bit lower. Will post better numbers when the film is dried and I can measure it and scan it.
- 300ml water @ 20C
- 6ml PC-512 concentrate
- 1.2g sodium metaborate
View attachment 332382
The idea then would be to try to make a single concentrate with that amount of metaborate. Assuming that it doesn't change its pH substantially when combining with glycol in heated solution.
Not sure how it is in the USA, but here, sodium carbonate is found in pool supply stores as pH+. Sold in 5-kg buckets.What is the common or brand name for sodium carbonate at the grocery store? I need to buy another batch for D-72.
Yeah, I have a big bag of ascorbic acid and no ascorbate. I did not look into it as a result. But it's a good point.Good work. I'm sure it has occurred to you to use sodium ascorbate, if it is soluble in glycol, in order to cut down on the amount of alkali needed. The downside is a form of ascorbate that is less common.
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