Potassium Hydroxide in Parodinal?

ulysses said:

I just ordered some R09 (Rodinal) from Freestyle and the invoice says "Potassium Hydroxide". All of the Rodinal formulas I have specify Sodium Hydroxide. I have potassium hydroxide, which apparently can be shipped easily (at least within the states) but DEA forms are required to sell/ship sodium hydroxide. I have a bunch of acetaminophen capsules, too, since I was planning to test Parodinal against the "real" thing. Can I use potassium hydroxide in place of sodium hydroxide to make Parodinal? If no one knows (or no one replies) I'll give it a try and report back.

Ulysses

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I wonder if paracetemol can be obtained in bulk powder form. getting it from the capsules is laborious.

[QUOTE = "Donald Qualls, gönderi: 2308070, üye: 4594"] Tamam, işte Parodinal'de geliştirilen birkaç örnek.

251.978 [/ ATTACH] [= tam ATTACH]

Pentax Spotmatic SP, Super Takumar 50mm f / 1.4, Tri-X, Parodinal 1:50

251.979 [/ ATTACH] [= tam ATTACH]

Canonet 28, .EDU Ultra 100, EI 400, Parodinal 1:50

251.980 [/ ATTACH] [= tam ATTACH]

Zeiss Ikon Ideal, 13,5 cm f / 4,5 Tessar, Fomapan 100, Parodinal 1:50 [/ QUOTE]
Thank you very much for your kindness. I guess I'm tiring you with my questions and requests. But your photos are very good in my opinion. Parodinal seems to have done a good job. When I do my parodinal, I will immediately put a film on my camera and take a picture and test the formula. I have Olympus OM10 and Lubitel 166B cameras. Now I have 35mm Ilford pan f plus 50, hp5 400 films and old dated kodak T400cn b & w medium format film. Last week I developed a reel T400cn with Ilford PQ Universal. 8 minutes at 1 + 19. Some shots were good, but generally the film was overly developed. When I prepare the solution, I will use it in developing the film.

RalphLambrecht said:

I wonder if paracetemol can be obtained in bulk powder form. getting it from the capsules is laborious.

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Hi. I live in Turkey and I ordered paracetamol powder form. Still, it's hard to find in powder form.

Sorry guys, missed those comments. The extra stick-on label only had warnings about child access etc and this statement about KOH 41g/L. Nothing else Anon Ymous.
I recall posting the comment on a discussion with Pat Gainer and I said what you said.

Parodinal doesn't use sodium carbonate -- that would be an accelerator alternative to sodium hydroxide (the core ingredient in your drain cleaner), borax, metaborate, or even just sulfite (D-23 uses sodium sulfite as both preservative and accelerator). If you had p-aminophenol in that form, you could probably make a (rather slow) developer with it using sodium carbonate, but it wouldn't have any advantages over Parodinal other than having less hazardous ingredients. But starting from paracetamol/acetaminophen, you need the very high pH to convert the pain medication into the developing agent -- I'm pretty sure sodium carbonate, at 10.6, isn't alkaline enough.

The soda ash for swimming pools is just the thing for making Caffenol. Caustic Soda is the right stuff for Parodinal. BTW, you can probably get sodium thiosulfate as chlorine reducer at the pool store, too -- and there's your simple fixer. The drain cleaning liquid you used probably contains a lot of sodium silicate (to protect pipes from the sodium hydroxide), which might have effects on development (I'm not sure).

It's possible to use Parodinal without the sulfite; after dilution, it has very low sulfite concentration in the working solution even at 1:25. However, it won't last reliably, I'd be suspicious after even three days. You could try reducing the quantities to fit with two Panamax tablets to make concentrate suitable for a single developing tank fill -- you'd wind up with about 17 ml of concentrate, which would be enough to dilute 1:25 into 425 ml of working solution, or 1:50 into 850 ml (the former a little more than a 35mm tank fill, the latter as much as 3x 35mm or more than needed for a 120 roll). You'd mix the stuff, cool it (after mixing the caustic soda), and use it as soon as the solution turns a distinct pink -- might be good as soon as it's down to room temp, since I recall the pink coming on almost instantly while adding the lye. You do need to make this as concentrate, then dilute; if you use working solution volume, the alkali probably won't be strong enough to convert the n-acetyl-p-aminophenol into p-aminophenol in a reasonable time.

I haven't used it without preservative, because I have fairly easy access to sodium sulfite in the USA, but I have no reason to believe it wouldn't work -- but I wouldn't expect it to continue to work for more than a day or so.

BTW, the Calcium Hardness Decreaser seems to be similar to Calgon; it would be useful in mixing chemicals with tap water rather than distilled, but I haven't any idea how much you'd need.

Thanks Donald. I'll try to get hold of some Sodium Sulphite but in the meanwhile, will have another play around with my 'Sparkle'

Nige said:

Thanks Donald. I'll try to get hold of some Sodium Sulphite but in the meanwhile, will have another play around with my 'Sparkle'

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You might check your pool supplier -- sodium sulfite is an alternative for sodium thiosulfate as a chlorine reducer. Its main advantage, in that application, is that it's less toxic than thiosulfate (doesn't take much of the latter to kill a dog, for instance -- where sulfite takes a lot more to do the same dirty deed). I've also seen it appear on labels as a food preservative, so it might be sold for that purpose (though for things like home sausage making and canning, sodium nitrite is more common). Finally, there's a conversion ratio available to substitute sodium metabisulfite, which is commonly used in wine making, so likely to be available at home brewing suppliers. Expensive, compared to bulk sodium sulfite, but it would work -- and with the dilutions common for Rodinal work-alikes, the per-roll cost would still not be terrible.

Hello Donald. Can I use tap water for Parodinal? How were you doing? Thanks.

Olympus17 said:

Hello Donald. Can I use tap water for Parodinal? How were you doing? Thanks.

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Depending on your tap water, you might get away with it, but Parodinal doesn't contain any sequestration additives (like commercial developer mixes would), so I'd recommend starting with distilled or deionized water for best storage life. I've mixed my stock solutions and concentrates with only distilled water since coming back to the darkroom the first time, in 2003; I use tap water for dilution (to one-shot working solution), and for washing, but even for commercial chemicals I prefer to mix with high purity water. Just to be sure.

Thank you Donald. My first job tomorrow will be to buy distilled water. I want to ask you a question that has troubled my mind, is 10g of Potassium Bromide too much for 200ml parodinal? You said 5gr for 100ml in your recipe.

I found 5 mg in 100 ml about right -- that'd be 50 mg/L, which is a lot, but this is an optional add-in to reduce fog. What you could do is leave it out, test the developer, and then add some if you find it's needed for fog control. If you're using fresh, in-date film, you may not need any.

I am using Kodak t400cn film dated 2005. Film C41 developer compatible. But I developed 2 rolls with PQ universal. The first was 8 minutes at 1 + 19 dilution. The result was generally very dark except for two squares. The second was 6 minutes at 1 + 19 dilution. This was relatively much better. But it still seems dark to me. I intend to reduce the development time a little more. About 5 minutes. Could you have any advice on this? Thank you.

Hi Donald. I did Parodinal tonight. I prepared 200 ml of solution according to the measurements you gave for 100 ml. I just used 5 g of Potassium Bromide. I dissolved sodium sulfide in 125 ml of water. But at 110F this was very difficult. Can I use higher temperature water? Then I dissolved sodium hydroxide and paracetamol in 75 ml of water and mixed them together. I will wait three days now. I hope I will succeed.

For the sulfite alone, you can use hotter water without harm -- many home water heaters, however, are limited to 120F or so for safety. If you're heating distilled in the microwave, there's no such limitation, of course.

One variation that produces the same end result is to dissolve the acetaminophen first, then the sodium hydroxide, and only then the sulfite. This lets you use more starting water if needed (avoids the potential for the lye boiling the water), heats the water for the sulfite addition, and lets the sodium hydroxide work on the acetaminophen for a short time before the sulfite gets in the way.

The three day wait is to allow the acetaminophen to break down to p-aminophenol, and isn't a hard and fast time; once the solution becomes pink, it should be ready to use.

I'm going to look at the solution on Saturday. I hope it turns pink. I put it in a green colored bottle. I keep it in a dark and cool place. I'll share a photo of you when it's ready. Thank you very much for your help.

Olympus17 said:

I'm going to look at the solution on Saturday. I hope it turns pink. I put it in a green colored bottle. I keep it in a dark and cool place. I'll share a photo of you when it's ready. Thank you very much for your help.

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You probably won't be able to see the solution color (other than as a darkening) through green glass, but after three days, it should be ready. The other test is to put a thermometer or other reasonably inert (or disposable) object into the solution and transfer a single drop to a cut off film leader (in the light): it should turn a full, deep black in seconds (the concentrate is 25-50 time stronger than working solution).

RalphLambrecht said:

I wonder if paracetemol can be obtained in bulk powder form. getting it from the capsules is laborious.

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I get it here in India

Sidd said:

I get it here in India

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I've tried to find an overseas source that will provide it, but I got nowhere. I could probably buy a kilo for what I pay for a couple hundred caplets locally (though now, shipping, tariff, and import duty might make it impractical).

Donald Qualls said:

I've tried to find an overseas source that will provide it, but I got nowhere. I could probably buy a kilo for what I pay for a couple hundred caplets locally (though now, shipping, tariff, and import duty might make it impractical).

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I can provide you the contact of the chemical seller in India, who has pure paracetamol in stock. However, nowadays you have to pay 50% more in tariff!

Aren't paracetamol and acetaminophen the same?

Chuck1 said:

Aren't paracetamol and acetaminophen the same?

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Different (generic drug) names for the same compound... N-Acetyl-4-aminophenol (CAS number: 103-90-2).

There are many US suppliers which ones will sell to an individual will take a few phone calls/emails. Don't know about the EU or the rest of the world.

Of course, this thread is five years old so today's responses may be moot! Just saying.

Chuck1 said:

Aren't paracetamol and acetaminophen the same?

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Yes

If you are based in India like Sidd or purchasing from Indian chemical labs, you can go for 4-aminophenol directly and make Rodinal substitutes with it. Buying Paracetamol makes sense only when you can't get 4-aminophenol easily.