Homebrew Parodinal - GenZ to OGs

Hi OGs, first thread in the forum!
I've been trying to brew my own Parodinal, scanning through a bunch of youtube channel, then ended up with Pictorial Planet and apenasimagens.com recipes.
The problem is, yes, both developer works, but the images are harsh in contrast, the details lost its sharpness, and it doesn't work like the original dev chart for Rodinal. Oh and the cloudy, muddy, milky stuff at the bottom :/ so annoying.

I'm using:
- 250ml of distilled water
- 15g of crushed tylenol
- 50g of Na2SO3
- 20g of NaOH

Any advice to improve this fantastic recipe would take me 1 step closer to the fully analog journey. Thank you OGs!
Btw I'm 23, stupid and brain-rotted so please be nice

Have you let the mixture sit for at least a couple days? The hydrolysis reaction that turns Tylenol into 4-aminophenol takes a bit to complete.

That's the same recipe I used. At 1:25 and 1:50, it worked exactly like Rodinal. The temperature of your developer needs to be around 20 degrees C. If it's higher, that will cause increased contrast due to overdevelopment.

More details about how exactly you are using it would be helpful.

phuc said:

Hi OGs, first thread in the forum!
I've been trying to brew my own Parodinal, scanning through a bunch of youtube channel, then ended up with Pictorial Planet and apenasimagens.com recipes.
The problem is, yes, both developer works, but the images are harsh in contrast, the details lost its sharpness, and it doesn't work like the original dev chart for Rodinal. Oh and the cloudy, muddy, milky stuff at the bottom :/ so annoying.

I'm using:
- 250ml of distilled water
- 15g of crushed tylenol
- 50g of Na2SO3
- 20g of NaOH

Any advice to improve this fantastic recipe would take me 1 step closer to the fully analog journey. Thank you OGs!
Btw I'm 23, stupid and brain-rotted so please be nice

Click to expand...

Parodinal is my normal working developer, I use a version that uses potassium metabilssufite instead of the the sodium sodium sulfite, as here in portugal is much much easier and cheaper to find the first. You may want tho check this blog: https://caffenolcolor.blogspot.com/, as it contais lots of recipes for alt. devs.

Here is a clear version:
Develop for 10% longer than Rodinal.

thinkbrown said:

Have you let the mixture sit for at least a couple days? The hydrolysis reaction that turns Tylenol into 4-aminophenol takes a bit to complete

Click to expand...

Yes, I let it sit for 72hrs before using it.

Chromium VI said:

Parodinal is my normal working developer, I use a version that uses potassium metabilssufite instead of the the sodium sodium sulfite, as here in portugal is much much easier and cheaper to find the first. You may want tho check this blog: https://caffenolcolor.blogspot.com/, as it contais lots of recipes for alt. devs.

Click to expand...

Definitely gonna check out your website, thanks a lot OG. But potassium metabilssufite is hard to reach here in Asia, a little expensive. I'll read your blog and tryna find out something that work.

Alan Johnson said:

Here is a clear version:

Parodinal with potassium bisulfite

Sodium hydroxide is caustic ,hazardous: http://www.ccohs.ca/oshanswers/chemicals/chem_profiles/sodium_hydroxide.html Parodinal is a homebrew developer made from Paracetamol/Tylenol (aka acetaminophen) capsule contents which are reacted with sodium hydroxide to produce p-aminophenol which is...

www.photrio.com

Develop for 10% longer than Rodinal.

Click to expand...

Potassium-related chemical is costly here OG. But I've checked the link and the conversation there opened up a lot of options for replacement. Thank you!

I'd be curious to see the results you're getting since the formula you're using is the same as I've used and my results are indistinguishable from real rodinal.

phuc said:

Definitely gonna check out your website, thanks a lot OG. But potassium metabilssufite is hard to reach here in Asia, a little expensive. I'll read your blog and tryna find out something that work.

Click to expand...

Just to be fair to the author, the blog isn't mine, it belongs to Henrique de Sousa, a Leiria based photographer.

For the hydrolysis of paracetamol to 4-aminophenol to proceed, a large excess of hydroxide is required. The problem is that you don't really know when the process has finished or how successful it has been. Also, Parodinal is not Rodinal. If the excess hydroxide is not neutralized, it remains as one of the differences that can lead to higher contrast. In addition, the sulfite concentration is very high - unless one of the components is replaced with a potassium salt, crystallization will occur. When dissolving the sulfite, add it gradually in portions rather than all at once to ensure complete dissolution.
72 hours should be sufficient for the hydrolysis, but it’s still unclear what exactly is happening. Did the mixture turn red in color?

You can make do with less sulfite, I mixed mine with just 20g to 250ml and it still works fine after 2 years.

Hi OGs, I came back with the result. These are, so far, the 2 batches that worked.

The darker one I do exactly like DrFrakenfilm tutorial, the result came out with a thick layer of milky stuff that I told ya. It worked, but somehow stronger than the Rodinal chart on massive dev chart, with the same amount of time it renders harsh contrast and big big grains

The lighter one, I split them in half.
- 100g of water was used dissolve 32g of Na2SO3
- 50g of warm water (50 - 60°C) was used to dissolve 15g of crushed tylenol, then I filtered it out through a coffee filter paper.
The filtered tylenol now pour into a 100g of water + NaOH (I wait until it cool down to room temperature before I pour Tylenol in)
- I mixed the two together and waited for 72h then got the result.

With this one, it's weak. I think some acetaminophen didn't pass the filter paper. I use it to develop a Ilford Pan 100, which should be 9 minutes, but I left it there for 10,5 minutes and it still dark. The grain is awful guys, I'll attach the photo.

I think I'll do more research next time, there's still something missing that I don't know it yet. Thank you guys a lot for helping me.

@phuc: If you can buy small amounts of p-Aminophenol (CAS no. : 123-30-8) or p-Aminophenol Hydrochloride (CAS no. : 51-78-5), you can make a Rodinal substitute (Gainer's EZ-Rodinal for instance) without much hassle.

Hello, you are getting overactivity and large grains on the film due to an excessive amount of sodium hydroxide. For the second attempt - Tylenol should not be filtered. This is because most of it cannot dissolve, and during filtration you remove it along with the inert particles.

Thank you @Raghu Kuvempunagar !
I've just ordered it, kinda pricy but I think it will worth it!

@lamerko yeah I do think filter the tylenol was a bad idea, but there must be some way to remove the starch and wax in the capsule aight? Btw I only use 8g of sodium hydroxide for the lighter batch. Maybe because the lack of acetaminophen so the sodium hydroxide cannot fully react, that's why it creat excessive sodium hydroxide I think.

The inert fillers from the tablets can be removed at the very end, once the whole process is complete and you have a working concentrate. This is because Tylenol/paracetamol, as well as the base p-aminophenol, have very low solubility in water. Initially, when you add the crushed Tylenol tablets, only a small portion will dissolve, so you shouldn't filter at the beginning.
For everything to work, you need to cleave the acetate group from Tylenol via hydrolysis using a large excess of hydroxide. If there isn’t enough, the hydrolysis will be too slow, incomplete, or may not occur at all. The goal is to form the soluble p-aminophenolate salt, which in this case requires an additional 5-6 grams of sodium hydroxide.
By the way, once the whole process is complete, you can slightly adjust the pH to account for the large excess of hydroxide.”