Real Agfa formulae:-)

Photo Engineer said:

As you said previously, it can be difficult. Ammonium Hydroxide is one of those that is difficult due to having densities lower than 1.0.

PE

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According to Wikipedia:

At 20 °C, the relationship between specific gravity (s.g.) (relative density) and degrees Baumé is

For liquids denser than water: s.g. = 145 ÷ (145 - degrees Baumé);
For liquids less dense than water: s.g. = 140 ÷ (degrees Baumé + 130).
An older version of the scale for liquids heavier than water, at a reference temperature of 15.5 °C, uses 144.32 rather than 145.

Hydrometers for measuring densities less than 1.0 are easy to find. API gravity hydrometers (American Petroleum Institute) are typically less than 1.0, and sometimes have SG scales as well.

And my 18th Ed. CRC from 1932 lists degrees Baume for Aqua Ammonia and displays it for % Ammonia as well as Sp. Gr.

And to make life even easier many Photo chemicals are sold as solutions, and the data-sheets show the Specific Gravity's.

Ian

An aside: in early manuals, Agfa referred to p-aminophenol as Rodinal, a proprietary name for the developing agent. That was distinct from Rodinal developer.

Kirk Keyes said:

According to Wikipedia:

At 20 °C, the relationship between specific gravity (s.g.) (relative density) and degrees Baumé is

For liquids denser than water: s.g. = 145 ÷ (145 - degrees Baumé);
For liquids less dense than water: s.g. = 140 ÷ (degrees Baumé + 130).
An older version of the scale for liquids heavier than water, at a reference temperature of 15.5 °C, uses 144.32 rather than 145.

Hydrometers for measuring densities less than 1.0 are easy to find. API gravity hydrometers (American Petroleum Institute) are typically less than 1.0, and sometimes have SG scales as well.

Click to expand...

Kirk;

When I did a search for Baume several years ago, I found no wikipedia entry or indeed no wikipedia. The results I did turn up were those that gave both methods of conversion including 2 for heavier than water and 2 for lighter than water.

Unfortunately, one cannot say which method was used in the above, and the conversion is not very straightforward according to some of the literature I had.

Fortunately, I have a rather complete set of hydrometers that are handy when needed!

After several hours thinking this over, I realized that every encounter with solutions specified in Baume units ended up being an unsatisfactory formula. In some cases, the conversion (as best I could do it) was either wrong or virtually impossible. I have become kind of negative or uncomfortable overall when I use Baume.

PE

I can't say as I understand most of this but Bernard e Jones' Encyclopedia of photography in 1911
Rodinal, ...a one shot developer,... introduced by Andresen... formerly under the name of unal...
The Chemische zeitung formula
Potass. metabisulphite or sodium sulphite 3 parts
Para-amido-phenol Chlorohydrate 1 part
Sodiun hydrate (sat sol.) Q.S.
Hot distilled water 10 parts
There then follows a long discussion of how to use it.

With everyone rushing into the breach, Ian will never publish his formula.

PE

hell, I was thinking of taking a stab at it too!

Photo Engineer said:

With everyone rushing into the breach, Ian will never publish his formula.
PE

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Still working on it I've got 37 pages of notes so far, and 3 separate spreadsheets

Ian

Just for Ron (PE)

I think Patrick "Gadget" Gainer has come closest to publishing a rough Rodinal (Agfa/A&O) substitute with this:

To about 750 ml of water at room temperature, add
p-aminophenol...............38 grams
sodium sulfite (anh)........160 grams
sodium hydroxide............23 grams
Add water to make 1 liter.

On the right track, you need to use the free base and an excess of Hydroxide unlike the older R09 formula which has nearly 20% more p-Aminophenol and also requires using at a higher concentration to get equivalent results. (The concentrate has recently been changed).

In a post about Patrick's version a comment was made about the pH at 1:50 being roughly 11.6, Agfa Rodinal has a stock concentrate pH of 14 and a dilute pH of 11.55 so if this is the case Patrick's formula is about right, except too little Sulphite and there's no Bromide or anti-foggant.

This is what I would use as a starting point:

Rodinal Sustitute

p-Aminophenol.(free base) ................... 41 g
Potassium sulphite (anh) ..................... 348 g
Potassium Hydroxide ........................... 27 g
Potassium Bromide ............................. 10 g
Benzotriazole 1% ............................... 10 ml
EDTA Na4 (optional) ........................... 6 g
Water to make .................................. 1 litre.

If necessary adjust to pH 14

Some notes;

Agfa Rodinal has always contained the p-Aminophenol free base although the Hydrochloride was used initially in the preparation of the free base.
The balance of the Bromide & Benzotriazole may need adjusting.

Agfa's modern Rodinal 1964 onwards uses an excess of Hydroxide and as a consequence is more active despite a lower level of p-Aminophenol than the previous formulae. Calbe R09 has a pH of 11.8.

The mixed developer should be left a couple of weeks before use.

Ian

Thanks Ian. I was unsure of Patricks formula as the "real" Rodinal tests strongly for Potassium and Patrick's formula has none!

Of course, the real Rodial is hard to test for Bromide, but does not appear to have any significant amount. So, this is a maybe. It may be there but may be at lower concentration than you note above.

PE

The Bromide in genuine Rodinal is possibly higher than the figure I've used, it's listed on the MSDS as between 1-5% so it's unlikely to be lower. I took the low figure because it's easy to add more when testing but you can't take it out. The WWII formula used 0.8% Bromide but was less active.

One thing I've noticed with MSDS's from nearly all photochemical manufacturers is that the actual amounts do fall between the listed parameters, of course this is easier to check when a formula has been published.

Ian

I just opened a sealed box of Ansco Superpan Press sheet film that expired in 1948. Inside was a info sheet and on the back is a formula for Ansco 47. Anyone here care? I found a recipe for it on a quick search and all is the same except the Bromide. Is this old enough that I would stay out of trouble if I scanned and posted it, or would that be wrong?

Photo Engineer said:

Thanks Ian. I was unsure of Patricks formula as the "real" Rodinal tests strongly for Potassium and Patrick's formula has none!

Of course, the real Rodial is hard to test for Bromide, but does not appear to have any significant amount. So, this is a maybe. It may be there but may be at lower concentration than you note above.

PE

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I did post somewhere as alternate the formula with substitution of equimolecular weights of the potassium salts. Potassium sulfite is so much more soluble than the sodium that relatively more can be dissolved. I don't know if that is very significant seeing that the working solution has so little sulfite.

I made some of my Rodinal Expedient a year or so ago and it has not turned the strong color. I don't remember what I might have done differently, but the latest batch is quite dark. It all seems to work the same.

It's online already

All the Agfa Ansco / GAF Formulae are posted on a wide variety of website many are here on APUG. There are complete Agfa Ansco books of Formulae available as PDF's they are well out of copyright.

I have just corrected one site which had listed the Avoirdupois 12 grains as 12 gr instead of 0.8g

AGFA/ANSCO 47
Film developer
Water, 125F/52C 750 ml
Metol 1.5 g
Sodium Sulfite (anhydrous) 45 g
Sodium Bisulfite 1 g
Hydroquinone 3 g
Sodium Carbonate (monohydrate*) 6 g
Potassium Bromide 0.8 g
Cold water to make 1L

* = 5 g Sodium Carbonate (anhydrous)

Mixing instructions: Add chemicals in specified sequence.

Dilution: Use undiluted
Starting point development time: 5 - 8 mins.
Notes: Long shelf life.

gainer said:

I did post somewhere as alternate the formula with substitution of equimolecular weights of the potassium salts. Potassium sulfite is so much more soluble than the sodium that relatively more can be dissolved. I don't know if that is very significant seeing that the working solution has so little sulfite.

I made some of my Rodinal Expedient a year or so ago and it has not turned the strong color. I don't remember what I might have done differently, but the latest batch is quite dark. It all seems to work the same.

Click to expand...

Just about to post in the Formula section with mention of both your formula

Ian