Rodinal precipitate

[Philippe-Georges]

Last night I developed a FOMAPAN 400/120 at 1600ASA in Rodinal 1+50 for 25 min 20°C (see the massive developing chart).
As advised by Patrick Gainer, I added 1 gr/litre Borax to the work dilution (*).
The results ware not that good but usable. It looks under developed but it might be poorly exposed as the pictures were shot in extremely poor light conditions (hence the 1600ASA).

(*) Concerning the Borax, I took the liberty to attach a nice text written by Patrick Gainer about his vision on Rodinal.
I must admit that I learned a lot from his vision and knowledge he broadcasted in his every comprehensive and pleasant to read writings.
I hope that by doing this I don't violate the rights of Patrick Gainer!

 

[Alan Johnson]

I don't believe Gainer ever wrote up his Rodinal/sodium ascorbate/ borax formula with quantities all in one place.
This seems to be the nearest:

Rodinal Substitutes?

Gerald, please note the fact that bromide was added to Rodinol when they stopped using the hydrochloride salt of the pAp. This event is not insignificant IMHO. PE I think that may be a coincidence since chloride ion is such a feeble restrainer.

www.photrio.com

The borax addition is to stop the ascorbate from causing fog at the pH of Rodinal.

 

[JPD]

As I understand this and parodinal is that the crystals that form on the bottom the bottle, should be left in the solution.

That's my understanding as well, and that decanting might affect the longevity in a negative way.

 

[Philippe-Georges]

That's my understanding as well, and that decanting might affect the longevity in a negative way.

I only decant when mixing the concentrate in the water to make the work solution, the crystals remain in the bottle of course.

I have been rummaging in my computer and found the pdf with the whole text by Patrick Gainer, dating from 2006 the year after AGFA's demise, here is the full original text.

Please, and I do insist, don't see this as an idolatry!

Along this search, I found a text coming from the Photographers Formulary on their Rodinal, I show it here in a manner of additional information, and that's why I add a text about the Paracetamol developer too, which could be considered as an Rodinal alternative.

PS: BTW, Mr. Alan Johnson, I don't understand what you don't believe about Patrick Gainer, may ask for some enlightenment please?

 

[Alan Johnson]

Your link "Adding sodium sulfite..." comment 2 gives the amount of sodium ascorbate to be added. It is the definitive article I could not find, what was the source?
The history of Parodinal is now lost due to broken links:

Potassium Hydroxide in Parodinal?

I just ordered some R09 (Rodinal) from Freestyle and the invoice says "Potassium Hydroxide". All of the Rodinal formulas I have specify Sodium Hydroxide. I have potassium hydroxide, which apparently can be shipped easily (at least within the states) but DEA forms are required to sell/ship...

www.photrio.com

But your link "Paracetamol developer.." was early work on this.

 

[Philippe-Georges]

Your link "Adding sodium sulfite..." comment 2 gives the amount of sodium ascorbate to be added. It is the definitive article I could not find, what was the source?
The history of Parodinal is now lost due to broken links:

Potassium Hydroxide in Parodinal?

I just ordered some R09 (Rodinal) from Freestyle and the invoice says "Potassium Hydroxide". All of the Rodinal formulas I have specify Sodium Hydroxide. I have potassium hydroxide, which apparently can be shipped easily (at least within the states) but DEA forms are required to sell/ship...

www.photrio.com

But your link "Paracetamol developer.." was early work on this.

I don't recall the source as it is nearly 16 years ago...
I downloaded the article, at the time and saved it as a pdf, what I always do with documents I want keep for long and eventually print them..

 

[Alan Johnson]

Looks like you rescued Gainer's ascorbate addition to Rodinal formula from disappearing.
Regarding the crystals deposited I believe:
(1) Rodinal very slowly deposits potassium aminophenolate , probably a supersaturated solution.
(2) PaRodinal deposits sodium sulfite in the short term as the specified amount exceeds the solubility of sodium sulfite at room temperature. In the long term it may deposit sodium aminophenolate as well, may be supersaturated.

 

[Philippe-Georges]

Looks like you rescued Gainer's ascorbate addition to Rodinal formula from disappearing.
Regarding the crystals deposited I believe:
(1) Rodinal very slowly deposits potassium aminophenolate , probably a supersaturated solution.
(2) PaRodinal deposits sodium sulfite in the short term as the specified amount exceeds the solubility of sodium sulfite at room temperature. In the long term it may deposit sodium aminophenolate as well, may be supersaturated.

Perhaps it can be put amongst the other formulas on this forum?

 

[Alan Johnson]

Yes. May be of interest to some Rodinal users.

 

[ronald_south_africa]

A (Pa)rodinal calculator

Hi All, For those interested in making parodinal using paracetamol, see if the attached calculator is of any use, and give me feedback. Kind regards, dorff

www.photrio.com