This is a home-made equivalent of Rodinal, created by synthesizing the p-aminophenol from acetaminophen (paracetamol) using sodium hydroxide.


You will need the following chemicals:


Sodium sulfite can sometimes be bought as a meat-preserving agent or bottle-washing powder from a brewing-supplies store. The paracetamol is cheap, it's a commonly-available painkiller. Sodium hydroxide can be purchased as drain cleaner.

Optional Purification

The above process will leave you with filler powder from the tablets in your developer; it should just precipitate into the mud at the bottom, where you can avoid it when drawing off developer concentrate for use.

To avoid this problem, you can take the following optional steps:

This approach depends on the fillers used in the particular tablets you buy, and (assuming you don't have a means to condense and reclaim the isopropanol vapour) wastes a little alcohol.

Note that the paracetamol crystals are fairly pure and quite toxic at this concentration if you ingest more than a gram or two. Evaporating the isopropanol should obviously not be performed over a flame or at high temperature because of the fire risk.

If you can obtain paracetamol capsules, they may (depending on brand) contain pure crystalline paracetamol with no fillers and binders, which obviates the need for the separation process. Even better if you can just buy the paracetamol powder directly from a compounding chemist.

Keeping properties

Genuine Rodinal allegedly has no water and will keep indefinitely, whereas the water content of Parodinal may cause it to oxidise. The concentrate should keep for several months at least though.

Some developer will crystallise out at the bottom of the container; this should be retained as it will ensure that the mixture remains a saturated solution of p-aminophenol. Do not include the crystals when extracting concentrate for dilution, but give the bottle a good shake to get as much as possible back into solution.

Development times

The same development times as for Rodinal should be used.


Death by liver failure due to ingestion of paracetamol is slow (about a week), inexorable (you will know exactly what is coming) and very painful. Any more than about 1 to 2 grams can be very bad depending on your body size and the state of your liver.

Sodium hydroxide is quite dangerous to handle because it will turn your skin to soap (kiss those nerves goodbye!) and burn your eyes out on contact.

When mixed with water, sodium hydroxide releases heat and gas, so you need to mix the solution in a borosilicate (pyrex) container and not plain glass or metal. Always wear gloves and goggles when handling this chemical and do the mixing outdoors or in a powered fume cabinet.

Never add water to sodium hydroxide, always add the hydroxide granules slowly to the other solution.

Don't evaporate alcohols using a flame. Methanol fumes are highly toxic.

Wear at least some nitrile or vinyl gloves and splashproof goggles for the whole manufacturing process. The resulting developer concentrate is still caustic due to the excess hydroxide, so don't touch that either.

If the developer concentrate is to be disposed of, dilute it approx 100x with water before it goes down the sink. Normal use of the developer at typical dilutions of 1+25 or 1+50 and chasing it down the sink with with the film-wash water is sufficient dilution.


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