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Historic Rodinal Formulae

by KennyE

The original formula for Rodinal was first introduced to the American Photographer Community by Dr. James H. Stebbins in New York City, NY, on Sept 8th, 1891, two years before Rodinal was sold commercially in the United States. It was through Stebbins' actions that the formula for Rodinal was allowed to enter the public domain.

A US Patent was granted on June 28, 1892 to Dr. Momme Andresen, yet it was challenged and it was proven that the patent was not filed correctly. It was then the responsibility of United States Commence Department to rule over the issue before it. Their decision was to have Agfa publish their formula for one year, in the United States. So Agfa's Rodinal formula was published and was thereby made public domain.

The formulas listed below include the modern equivalents for each compound. p-aminophenol Hydrochloride is also known as 4-Aminophenol Hydrochloride or para-Aminophenol Hydrochloride. Some older formulae refer to non-HCI (non-hydrochloride) versions of this compound, or use older names such as para-Amidophenol.

Original Laboratory Formula (1891)

Water (125F/52C)- 750ml
Sodium Sulfite (dessicated) - 50 grams
Sodium Hydroxide - 25 grams
p-Aminophenol Hydrochloride - 5 grams
Water 1000 ml

After making the formula, there is not enough p-Aminophenol to give good overall development and contrast. It is recommended that 7 grams of p-Aminophenol be used.

Rodinal Production Formula (1893-1896)

Solution A:
Water (125F/52C) - 250 ml
Potassium Metabisulfite (dessicated) - 50 grams
p-Aminophenol Hydrochloride - 5-7 grams
Potassium Carbonate - 25 grams
Sodium Hydroxide - 25 grams
Cold water to make 500 ml

Decant the Solution into a clear glass capped bottle, shake the bottle, then loosen and re-tighten the cap and allow the solution to settle. The complete solution should age for 72 hours in dim or dark place, yet after the first 12 hours of settling, filter it through a sheet of white linen, re-bottle and then allow it to settle for the remaining 60 hours before use.

Rodinal Production Formula (1897-1915)

Solution A:
Water (125F/52C) - 800 ml
Sodium Sulfite (dessicated) - 150 grams
p-Aminophenol Hydrochloride - 20 grams
Potassium Carbonate - 25 grams
Citric Acid - 10 grams
Lithium Hydroxide - 8-15 grams
Cold water to make 1000 ml

Decant the Solution into a clear glass capped bottle, shake the bottle, then loosen and re-tighten the cap and allow the solution to settle. The complete solution should age for 72 hours in dim or dark place, yet after the first 12 hours of settling, filter it through a sheet of white linen, re-bottle and then allow it to settle for the remaining 60 hours before use.

NOTE: Solution B is presented for historical purposes only. It is optional, but should only be included if you are using p-Aminophenol instead of p-Aminophenol Hydrochloride. Solution B has no active function and is used as a coloring agent only.

Solution B:
Water (125F/52C) - 20 ml
Eosine - 10 ml
Cold water to make - 50 ml

Mix Solution B on the second day of the aging process. Allow Solution B to settle for 20-30 minutes first, to become uniform in color, then slowly add to Solution A until you see a color change of your liking.., then stop. Re-cap bottle and let stand for the remainder of the 72 hours.

Rodinal Production Formula (1924-1940)

Solution A:
Water (125F/52C) - 250 ml
Sodium Sulfite (dessicated) - 50 grams
p-Aminophenol Hydrochloride - 5-7 grams
Potassium Carbonate - 25 grams
Cold water to make 450 ml

Solution B:
Water (ice cold) - 50ml
Lithium Hydroxide - 8-15 grams

Slowly mix in the caustic solution (Solution B) with Solution A until the precipitate appears and then dissolves. If you have reached the end of the solution B on hand before the precipitate dissolves, continue to add the caustic material until the precipitate in Solution A is dissolved.

Now decant the Solution into a clear glass capped bottle, shake the bottle, then loosen and re-tight the cap and allow the solution to settle. The complete solution should age for 72 hours in a dim or dark place, yet after the first 12 hours of settling, filter it through a sheet of white linen, re-bottle and then allow it to settle for the remaining 60 hour before use.

Rodinal Production Formula (1941-present)

Solution A
Water, 165F/75C150 ml
p-Aminophenol Hydrochloride20 g
Potassium Metabisulfite60 g
 
Solution B
Cold Water150 ml
Sodium Hydroxide25 g
 
Final Mix
Cold water to make1L

For detailed mixing instructions please see the Rodinal Formula page

This is actually the complete 1891 proposed production formula, listed in the 1892 patent. That formula went into production 1941 to the present.


Agfa's advertisement publishing the formula for Rodinal (Paramidophenol), from Anthony's Photographic Bulletin, Vol. XXXIII, No. 1, January 1902.

Another "Rodinal" formula which appeared in American Annual of Photography, 1896.

The information contained in this article has been researched and provided by KennyE

 

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