Experiment with Jay DeFehr PG110B and DCM18/DCM20 developers

Moderator note: this thread was split off from another one: https://www.photrio.com/forum/threads/my-pc-512-borax-developer.195379

Alan Johnson said:

This is the formula using dimezone-s and 18g metaborate:

DCM18 one shot concentrate:

Propylene Glycol...........................80ml
Sodium metaborate.....................18g
Ascorbic acid...................................12g
Dimezone-S.....................................0.7g
Propylene Glycol to.....................100ml

It can be made in a container partially immersed in hot water. The
ingredients dissolve with stirring at 60C ,with some effervescence around 50C.

For use dilute 1+49 with tapwater.

Click to expand...

Hi, I found this formula in a search about phenidone-ascorbic acid developers. Sometimes I develop lot of whole-plate sheets and am interested in this kind of concentrates, often derived from Patrick Gainier tries.
I have been mixing a 12 y. old formula by Jay DeFeher https://flic.kr/gd/cXMbL :
PG110B
propylene glycol 100ml
borax 30g
scorbic acid 10g
phenidone 1g

as I read about these DCM20 and DCM18 formulas, and I have a lot of phenidone-B/Z ie. C10H12N2O CAS 2654-57-1, more active than phenidone-A, I went to mix DCM18. The idea being to use quite some of it, I mixed 200ml so 36g sodium metaborate, 24 ascorbic acid, 1,4 phenidone-B

I use a water-bath around 70°C and magnetic stirer.
With PG110B it takes some time but the borax then the ascorbic acid dissolve.
With this DCM18, sodium metaborate dissolves, it seem to reach point of saturation as a trace stays, neglieable, but then ascorbic acid didn't dissolve. After repeated long stirring and warmed a bit more around 90°C. The result is a creamy whitish emulsion, that decants after few hours, staying creamy, with glycol of course on top as it is light.

DCM18 vs. PG110B:





DCM18 decanted:





Anyway decided to try this. Shaked the small bottle well so to homogenize it. Used 2% solution with a sheet of old Agfa Mamoray (single-coated x-ray). Made 300ml, ie. 6ml seringed of this cream.

This is the developed sheet:



not printing to paper, went digital in order to have an idea. V700 scan at 2400 dpi and ColorPerfect inversion

800x JPG:



detail:




so this creamy stuff seams useable. Yet I prefer to obtain a soluted concentrate instead. Was expecting dissolution to be easier than in the case of borax.

srardnec said:

Hi, I found this formula in a search about phenidone-ascorbic acid developers. Sometimes I develop lot of whole-plate sheets and am interested in this kind of concentrates, often derived from Patrick Gainier tries.
I have been mixing a 12 y. old formula by Jay DeFeher https://flic.kr/gd/cXMbL :
PG110B
propylene glycol 100ml
borax 30g
scorbic acid 10g
phenidone 1g

as I read about these DCM20 and DCM18 formulas, and I have a lot of phenidone-B/Z ie. C10H12N2O CAS 2654-57-1, more active than phenidone-A, I went to mix DCM18. The idea being to use quite some of it, I mixed 200ml so 36g sodium metaborate, 24 ascorbic acid, 1,4 phenidone-B

I use a water-bath around 70°C and magnetic stirer.
With PG110B it takes some time but the borax then the ascorbic acid dissolve.
With this DCM18, sodium metaborate dissolves, it seem to reach point of saturation as a trace stays, neglieable, but then ascorbic acid didn't dissolve. After repeated long stirring and warmed a bit more around 90°C. The result is a creamy whitish emulsion, that decants after few hours, staying creamy, with glycol of course on top as it is light.

DCM18 vs. PG110B:

DCM18 decanted:

Anyway decided to try this. Shaked the small bottle well so to homogenize it. Used 2% solution with a sheet of old Agfa Mamoray (single-coated x-ray). Made 300ml, ie. 6ml seringed of this cream.

This is the developed sheet:

not printing to paper, went digital in order to have an idea. V700 scan at 2400 dpi and ColorPerfect inversion

800x JPG:

detail:

so this creamy stuff seams useable. Yet I prefer to obtain a soluted concentrate instead. Was expecting dissolution to be easier than in the case of borax.

Click to expand...

Please check the quality of your metaborate.

I already pointed out that the concentrates were found to be unstable and not a satisfactory replacement for the 2 part form of PC-512 Borax given in post 1.
I suggest that if it is wished to further discuss the preparation and stability of such concentrates it might be better to start a new thread as it has been shown not to be relevant to the use of PC-512 Borax which is the subject of this thread.

Alan Johnson said:

I suggest that if it is wished to further discuss the preparation and stability of such concentrates it might be better to start a new thread

Click to expand...

Thanks for highlighting this; I've split off the post in question into a new thread.

@srardnec welcome to Photrio! Your example negative looks rather thin (underdeveloped) to me.

If all your chemicals are OK, it should dissolve if it is heated enough as others in that thread also found. But by Albada's rule for stability it is correctly predicted to crystallize eventually:

I tried the PCM18 and 20 versions of PC-512 and now just have a bottle of Karl's original PC-512 on my darkroom shelf. The PCM versions just didn't work out for me. I wanted it to work in the worst way since I have a lifetime supply of Kodak Kodalk (8-mol sodium metaborate) to use up, but it wasn't meant to be.
I'll throw another something out there to chew on when it comes to sodium metaborate. I recently mixed a batch of PMK pyro and had a devil of a time trying to get the sodium metaborate in solution B to go into solution. I'm now wondering if my "older than the hills" Kodak Kodalk is the problem being 8-mol and being exposed to the atmosphere too long. I did buy some new Sodium Metaborate, but haven't tried to make a new part B for PMK with it yet. The Darkroom Cookbook doesn't seem to say it makes much difference whether the sodium metaborate is 4-mol or 8-mol when making fixers or whatever.

Sidd said:

Please check the quality of your metaborate.

Click to expand...

just regular sodium metaborate from Merck. Kept dry, etc. I use it trouble free mostly for DK-25R replenisher for D-23 (20g/liter) and in a Diafine ersatz (15g/liter).
How is the condition of sodium metaborate chimically tested?



]

Google Gemini:
Sodium metaborate tetrahydrate (NaBO₂ · 4H₂O) is stable at ordinary temperatures under normal storage conditions, but it is not stable when exposed to air for extended periods.
Ataman Kimya +1
Key factors affecting its stability in air include:

• Carbon Dioxide (CO₂) Absorption: When exposed to the atmosphere for long durations, it readily reacts with CO₂ to form sodium carbonate and borax.
• Humidity Sensitivity:
  • In a humid atmosphere, the tetrahydrate (4 mol) can pick up moisture and convert to the octahydrate (8 mol).
  • In a warm, dry atmosphere, it may slowly lose its waters of crystallisation.

I suggest try making up the part A of Mocon developer from @albada.It is documented on here that it was free of crystals.

srardnec said:

Hi, I found this formula in a search about phenidone-ascorbic acid developers. Sometimes I develop lot of whole-plate sheets and am interested in this kind of concentrates, often derived from Patrick Gainier tries.
I have been mixing a 12 y. old formula by Jay DeFeher https://flic.kr/gd/cXMbL :
PG110B
propylene glycol 100ml
borax 30g
scorbic acid 10g
phenidone 1g

Click to expand...

You'll find that I linked that in the original blog post on PC-512 Borax as another similar developer. It uses more phenidone and less ascorbic acid than PC-512 Borax and will undoubtedly have the same problems that Alan found with the other two recipes in storage. Also, I do wonder about the resulting pH. I never tested PG110B, but PC-512 Borax tests around 8.6 (per @Alan Johnson 's better testing than mine) in solution. I suspect that PG110B is noticeably higher pH than that due to the very small amount of borax in solution. I would expect more fog. If you've tested it, it would be great to see negatives.

Alan Johnson said:

Google Gemini:
Sodium metaborate tetrahydrate (NaBO₂ · 4H₂O) is stable at ordinary temperatures under normal storage conditions, but it is not stable when exposed to air for extended periods.
View attachment 418986Ataman Kimya +1
Key factors affecting its stability in air include:

• Carbon Dioxide (CO₂) Absorption: When exposed to the atmosphere for long durations, it readily reacts with CO₂ to form sodium carbonate and borax.
• Humidity Sensitivity:
  • In a humid atmosphere, the tetrahydrate (4 mol) can pick up moisture and convert to the octahydrate (8 mol).
  • In a warm, dry atmosphere, it may slowly lose its waters of crystallisation.

I suggest try making up the part A of Mocon developer from @albada.It is documented on here that it was free of crystals.

Mocon -- XTOL-quality in a long-lasting concentrate

Mocon is a two-part developer consisting of a long lasting liquid concentrate and sodium sulfite powder used one-shot. It was originally intended to be an XTOL-clone, but it turned out to be not quite that. Mocon generally gives slightly finer...

www.photrio.com

Click to expand...

yes I am aware of the aerial decomposition of sodium metaborate into carbonate and borax. It is in the classic ilterature. It doesn't impact solubility. I was wondering about any saturation threshold with ascorbic acid or about an interaction sodium metaborate with ascorbic acid if any.
I know Mocon from the site of the author (i guess) Mark A. Everton, where I ended sometime years ago but never tried

I may try his concentrate but the issue I have by now is getting the ascorbic acid amount of PC-512 to dissolve in glycol. in Mocon, the proportion of ascorbic acid is even higher.
(I have 99,5% purity monopropylene glycol CAS 57-55-6 from Lubrisolve and 100% pure ascorbic acid from Buxtrade).

relistan said:

You'll find that I linked that in the original blog post on PC-512 Borax as another similar developer. It uses more phenidone and less ascorbic acid than PC-512 Borax and will undoubtedly have the same problems that Alan found with the other two recipes in storage. Also, I do wonder about the resulting pH. I never tested PG110B, but PC-512 Borax tests around 8.6 (per @Alan Johnson 's better testing than mine) in solution. I suspect that PG110B is noticeably higher pH than that due to the very small amount of borax in solution. I would expect more fog. If you've tested it, it would be great to see negatives.

Click to expand...

I will measure pH probably tomorrow when I will mix another PG110B bath.

I did read your page at https://imager.ie/a-simple-phenidone-ascorbic-acid-concentrate-developer/ two/three years ago but back then didn't try, as well as I didn't try Patrick Gainier formula. By now I tried Jay DeFehrer and Alan Johnson formulas because I am interested in an all in one concentrate similar HC-110, Ilfotec LC29, etc. Mainly a practically for when I have several whole plate sheets to develop. No need to use tons of sodium sulfite.

I have mixed you PC-512 and, with heating at 85°C and magnetic stirrer, it was tedious. Very long agitation with the magnetic stirrer while I was reading texts meanwhile. In the end i ended with a yellow colour, which should be oxydation. So I was wondering about its working.





================

I grabbed a Tessar lens, the Industar-37 300mm @f4,5 and some sheets of 2019 expired Agfa Mamoray cut to whole-plate, and took four shots.

this is x-ray film. I develop in tray with light constant agitation.
The reference developer was SD-28. ie. the Konica buffered D-76 with a bit of potassium bromide. 1/3 dilution of SD-28, for 5mn 15s.
Using this reference time, I developed one sheet in PG110B, one sheet in the creamy emulsion I got of DCM18.
2% dilutions ie. 6ml for 300ml water.

for the PC-512 borax, I used 6ml of the yellow concentrate, in 300ml of the borax solution, ie. 6,51 of borax in 300ml (21,7g for a liter).
It works much stronger/faster than the others, and reached a similar thickness quicky, so I took it into the stop bath after 2mn 15s.

there is more or less drags on some sheets, caused by insufficient soaking/washing of the halation. I developed quickly so didn't bother with soaking bath, just under the faucet

to get a quick idea, V700 scan @2400dpi and ColorPerfect inversion as grade 2 virtual printing. Resize the raw files to 800x600 as 90% jpg for display here.

the initial "reference" one in SD-28 (1/3 dilution, not 2% like wrongly written in the label):



PG110B:


DCM18:



PC-512:



a crop on the S of the camera name. 100% zoom in the raw file, saved lossless as PNG:

Great comparison, but you sure got a lot of streaking.

The PC-512 2% example even has some "Ghosting" in the example. Upper left corner is where it shows up.

Andrew O'Neill said:

Great comparison, but you sure got a lot of streaking.

Click to expand...

streaking yes a lot. As said I didn't care much about a good pre-soak/wash of the anti-halation, instead of a bath I washed quickly under the faucet both sides. Where there is most streaking is where I washed the quickest. Actually no pre-soak may have been better but for the sake of this quick comparison it doesn't matter.

What leaves me a bit perplexed is the time with PC-512. Because the mix of ascorbic acid into glycol turned yellow, I was supposing reduced activity due to oxydation, but in fact the sheet reached correct density under the red light after 2mn instead of 5mn with PG110B, DCM18 in same proportion 6ml concentrate for 300ml. The maths seems correct for mixing as per relistan instructions: 1:50 ie. 2% of concentrate, ie. 6ml for 300ml of a borax solution 21,7g borax/1liter. I didn't mix a liter but 6,51g borax in 300ml water, ratio kept.

ideally now I should use these times as starting point for further tries. I don't mind wasting lot of sheets of x-ray film, but with regular film I will use 4x5 sheets or cut 120 roll for 2x3 grafmatic holders.

srardnec said:

streaking yes a lot. As said I didn't care much about a good pre-soak/wash of the anti-halation, instead of a bath I washed quickly under the faucet both sides. Where there is most streaking is where I washed the quickest. Actually no pre-soak may have been better but for the sake of this quick comparison it doesn't matter.

What leaves me a bit perplexed is the time with PC-512. Because the mix of ascorbic acid into glycol turned yellow, I was supposing reduced activity due to oxydation, but in fact the sheet reached correct density under the red light after 2mn instead of 5mn with PG110B, DCM18 in same proportion 6ml concentrate for 300ml. The maths seems correct for mixing as per relistan instructions: 1:50 ie. 2% of concentrate, ie. 6ml for 300ml of a borax solution 21,7g borax/1liter. I didn't mix a liter but 6,51g borax in 300ml water, ratio kept.

ideally now I should use these times as starting point for further tries. I don't mind wasting lot of sheets of x-ray film, but with regular film I will use 4x5 sheets or cut 120 roll for 2x3 grafmatic holders.

Click to expand...

Given how much trouble you had dissolving/mix the concentrate, and the wildly differing time, I'd suggest you perhaps measured something wrong when mixing it. Which may also have had an effect on the result you got. Are these crops all the same density? Additionally... it does not normally start off yellow if you mixed it correctly.

This is what it should look like when mixed:

I'm also noticing in the comparison above that in the PC-512 Borax photo, you have a development streak right across the part of it that you cropped, which is not present in the other photos.