Alternative Parodinal recipes

First Alternative to Parodinal

First published on 29th March 2012

Parodinal, which original formula is from Donald Qualls and is reproduced at Digitaltruth Photo uses Paracetamol (Acetaminophen), sodium sulfite, sodium hydroxide and water.

I searched for sodium sulfite everywhere* and couldn't find, not even in old pharmacies. But I found metabissulfite which is used very much as preservative for the wine, I think. And cheap, 6 euro/kg. With a little help of search in interenet I came to the conclusion that metabissulfite reacts with sodium hydroxide and gives sulfite and water.

Na2S2O5 +2NaOH -> 2Na2SO3 +H2O

Calculating, I found 38g metabisulfite will make 50g sulfite. So, the Parodinal can be obtained as follows:

Solution A

Dissolve 20 g Sodium Hydroxide in 75 ml water and add 15 g smashed Paracetamol while the solution is still hot. Let cool.

Solution B

Dissolve 16 g Sodium Hydroxide in 75 ml water, let cool and add 38g smashed Sodium Metabisulfite. Let cool again.

Mix the solutions at room temperature, add water to make 250 ml

Normally it is said to wait 72 hours before using parodinal. Disrespect of this will cause no development.

* Meanwhile I found a supplier for Sodium Sulfite

Second Alternative to Parodinal

First published on 16-05-2012

Starting from this formula of Donald Qualls.

250 ml Water

30 tablets @ 500 mg Acetaminophen

50 g Sodium Sulfite (anhydrous)

20 g Sodium Hydroxide (anhydrous)

Mix in order indicated, let stand in sealed container 72 hours before using. Keep crystals from bottom of container with liquid when decanting, stir before drawing off concentrate for dilution. Use dilutions and times as for Agfa Rodinal. Use within 30 minutes of dilution.

Sodium Sulfite was not available for me at the time I used this alternative. So, I prepared following recipe:

Ingredients:

2x100 ml Water

20 g Sodium Hydroxide

30 tablets @ 500 mg Acetaminophen (Paracetamol)

40 g Sodium Carbonate (Potash)

500 ml Sulfurous Acid at 6% or equivalent to 30 g of pure acid

Preparation:

Solution A:

First of all, with a mortar, transform the Acetaminophen in powder.

Put 100 ml water in a beaker and 20 g Sodium Hydroxide inside and stir. While hot pour the acetaminophen and stir, one tsp each time until all powder is inside. This solution will be brownish. Let the beaker by side, let us call it beaker A.

Solution B:

Put another 100 ml water in another beaker and add 40g Sodium Carbonate and stir. It will not dissolve all but it doesn't matter. Now go on pouring the sulfurous acid slowly because you will get a lot of bubbles. In this reaction CO2 is produce in large quantity. You will end with less than 500 ml of a solution of Sodium sulfite. Put the solution in a pirex jar and heat it to get the CO2 out, stirring with a spoon. Let the solution cool down.

In a 500 ml bottle pour the content of beaker A. Then wash the beaker with solution B and pour in the 500 ml bottle until this is full. You may have more sulfite left but not much. You have now 500 ml of Parodinal. Let it rest for the same 72 hours before use.

When preparing the work solution, take in account that you end with 500 ml instead of the 250 ml of Donald's recipe. So, you need to double the concentration of the solution, instead of 1:100, use 1:50 and so on.

Third Alternative to Parodinal

First published on 16th May 2012

This recipe is a clone of the original RODINAL. Instead of p-aminophenol hydrocloride, I putted Acetaminophen, aka Paracetamol in a smaller proportion. Just after I tested it in a piece of film and no action. After some hours it already gave a black stain in a piece of negative.

Solution A:

150 ml hot water from tap

20 g Paracetamol

60 g Potassium Metabissulfite

Water to make 250 ml

Solution B:

150 ml water

40 g Sodium Hydroxide

Water to make 250 ml

Preparation:

Put 150 ml water @ 55ºC in a beaker. Smash with a mortar 40 x 500mg tablets of Paracetamol and pour to the beaker and stir to dissolve. It will not dissolve all. Smash 60g Potassium Metabissulfite and add to the solution of paracetamol. Add water to make 250 ml.

Put 150 ml cold water in a beaker and add 40g Sodium hydroxide. Stir and complete to make 250 ml. Let cool down.

Add solution B to A and stir. Let it stand for 72 hours before using.

4th Alternative to Parodinal or

645-Parodinal

This is a variation of the above formula. I increased the paracetamol to 40 g in order to have a stronger developer. Because each 2g of paracetamol need about 1 g of Sodium hydroxide, this one was also increased to 50 g. Metabisulfite stays the same.

 Solution A:

180 ml hot water from tap
60 g Potassium Metabisulfite
40 g Paracetamol

Solution B:

180 ml water

50 g Sodium Hydroxide

Preparation:

Prepare solution A with warm water and solution B with cold water. When preparing B it will warm up. Add it to A when still hot and bring all the mixture to a warm bath and stir until you get an homogeneous concentrate, several minutes are required. 

Add water to make 500 ml, let cool and store in an amber bottle well closed.