photographer's formulary paraminophenol

[Andrew Laverghetta]

Hi everybody. I got some of this stuff and mixed it together exactly how the thing says but it didn't seem to work out when I got the to precipitate part.

I'm asking anybody who has knowledge with mixing this stuff together for help. I don't assume that this stuff should look like beaten up eggs but it kinda does. I would assume I should be able to see through it but like I said, it's a pale yellow that looks kinda thick.

Thanks!!

Andrew

 

[Andrew Laverghetta]

here's an update...i tried to develop with that liquid that I got that I couldn't see through and it didn't end up doing anything because there was nothing on the film at all.

The way that it works I believe is that you mix up two solutions. Then you pour little by little of one solution into the other. I guess now I know that you pour one into the other and it starts out making a precipitate and then that pretty much takes over the whole thing and the whole mix because a precipitate, then eventually it starts clearing up but your supposed to leave just a very little of the precipitate or something. It mentions that it should take around 45mL to get to where it needs to be but I had already used that 45mL plus some more with no clearing up...so, I added the extra water and put it in two small bottles and that's when I did that test on the roll of film. Then I got frustrated and dumped those two containers into a large mixing one again and splash an unmeasured amount of that other solution into the big mix and it magically cleared up but I'm not sure if I put in too much or not. It definitly isn't as dark as the true rodinal...but I made a small dillution in a graduate and dropped a film leader in and it turned black so I guess it worked? It didn't turn black or develop at all when I tried that before.

I guess I don't know what to do, if I should try to use up more film to see if I can get this to work or if I should just spend more money and try to make more...which wouldn't be that fun.

Let me know what you think I should do.

 

[gainer]

My suggestion is to get 75 grams of p-aminophenol, the base, not the hydrochloride, 38 grams of potassium hydroxide, and 100 grams of potassium sulfite. Add the hydroxide slowly to 750 ml cold water. Add the other ingredients and water to make a liter. If there is a little precipitate after much stirring, don't worry. If there is no precipitate, don't worry. Treat it as Rodinal.

 

[Gerald Koch]

Starting with a solution of paraminophenol hydrochloride and potassium metabisulfite here's what you should observe.

1. At the start the solution is clear, no solid is visible. Clear means free from solids not colorless.
2. A you add the hydroxide more and more solid appears.
3. As more hydroxide is added there is a sudden darkening of the solution in which the solid appears.
4. At this point as more hydroxide is added the solid begins to dissolve.

The explanation --

Paraminophenol consists of a benzene ring on which there are two groups an -NH2 and a -OH group. The -NH2 group is alkaline in behavior and can react with acids to forms salts such as the hydrochloride while the -OH is acid in its behavior and can react with strong bases such as potassium hydroxide. Thus pap is said to be amphoteric. Rodinal in a concentrated solution of pap reacted with potassium hydroxide to form a compound called a phenolate. So named because phenol is the simplest compound to react in this manner. Now both the hydrochloride and the phenolate are very soluble in water while the free base, that is pap itself, is only sparingly soluble. As you go from the hydrochloride to the phenolate (by adding hydroxide) as you make Rodinal the free base first precipitates and the redissolves as the phenolate forms. This explains what you observe.

Hope this explains things.

There are many formulas for Rodinal and most of them are wrong including the one in Anchell and Troop.

 

[dancqu]

There are many formulas for Rodinal and most of them
are wrong including the one in Anchell and Troop.

My impression is that the formulas and their method of
compounding are designed to Maximise the concentration.
A Highly Concentrated, Rodinal type, p-aminophenol
developer is the result.

Compound for 1:4, 1:9, 1:19, etc dilutions. There
other challenges awaiting. Who needs a 75 grams batch
of a PAP developer? Dan

 

[Papa Tango]

Just keep adding

This is an old problem; one I just had a few weeks ago. Perhaps we should get PF to modify their instructions to reflect what is going on.

The solution is to keep adding the remainder of the hydroxide a few drops at a time until the solution begins to clear. Pay no attention the the measurements given for how much hydroxide it will take. They will do you little good.

As you drop in hydroxide a drop or so at a time as it clears, stop for a second and let it rest. The goal is to leave just a little bit of the participate in the bottom of the solution. Not much at all, just enough to see.

This is important as it affects the keeping ability of the stock solution.

The formula works really well once this little stumbling block is taken care of.

 

[Andrew Laverghetta]

yeah, I emailed them after I posted this and they said to try a roll through it which is obvious but they also said that it should be alright. I'll see if I can quote...

"Do a test roll and see how that comes out it should work fine."

When I put in more of solution B when I didn't really measure what I was doing it started to clear up almost instantly and I didn't see any of the precipitate remaining at all. I had also added the extra water beforehand to bring it to 250mL (since I got the smaller kit). Right now I have it in two small bottles, both are 125mL.

 

[Donald Qualls]

For about the price of the Formulary kit, you can go to Costco and buy 1000 tablets, 500 mg each, of acetaminophen, then the local grocery store and get a pound of Red Devil Lye, then a pool supply shop and get a pound of sodium sulfite (chlorine reducer, but be careful because sodium thiosulfate is also sold for this purpose) -- or you can order in the sulfite from a number of places, including Formulary, though shipping might blow your $20 budget.

When you have those ingredients, though, and some distilled water, you'll have everything you need to make Parodinal . Your pro-rated cost for the concentrate, which you'll use exactly like commercial Rodinal (but which only lasts about 90 days before it starts to weaken) will be about 30 cents for 100 ml, if like me you pay approximately $1 per gallon for the distilled water. And you'll have materials in hand to make several gallons of concentrate, though I'd suggest making it 100 ml at a time due to its limited life.

Of course, you won't be likely to use up the lye before you have to buy more -- it absorbs water and carbon dioxide from the air every time you open the container, and when it starts to clump badly you'll need to replace it because of the hazard of flying particles if you try to chip off bits -- but even if you figure that in, it will cost you less than a dollar for 100 ml of concentrate.

 

[pnance]

While I never had the chance to use original Rodinal, nor tried the re-issure by the new company, I have mixed Gainer's formula mentioned above and its everything he says. Mixes easily, no worrying about finding the precipatation point, just mix in the order given, use times as if it were Rodinal. Result, the negatives are great.

 

[dancqu]

If there is a little precipitate after much stirring,
don't worry. If there is no precipitate, don't worry.

I'd worry a little if no precipitate. NaOH in excess
will cause quite an increase in ph barring the presence
of any ph buffer. An exact strength NaOH or it's solution
is not to be taken for granted. Likely that is the reason
for adding the hydroxide slowly and until NEARLY
total dissolution has taken place. Dan

 

[gainer]

Surely, but if there is no precipitate, it is a simple matter to add a gram or so of p-aminophenol base to produce one, and IMHO the pH will be more consistent than the other way around. If you overshoot when adding the hydroxide in the usual method, you can do the same thing, but it's more nervewracking. Either way you do it, there is no need that I can see, either theoretically or in practice, to start with metabisulfite and p-aminophenol hydrochloride. If you start with the base and potassium sulfite, you will sure enough have a precipitate that you can munimize by titration if you wish, but you could as well calculate just how much hydroxide is needed to balance the equation and start with a little less, or put in the calculated amount and add a little excess p-aminophenol. What will be the difference, other than the lack of potassium chloride?