Rodinal concentration

Dave Krueger · Jan 22, 2007

I just got some Rodinol from photographer's formulary and noticed the formula they list in the spec sheet makes it half as strong as the formulas I see elsewhere in books and on the web. Specifically, I think the formula given in the Darkroom Cookbook (Anchell) and elsewhere shows it as having 100 g of Para-Aminophenol per liter whereas the Photographer's Formulary version has only 50g per liter.

When people talk about Rodinal, they also talk about development times at various dilutions. If the stock solution concentration from one source is different from that of another, how does one know what dilution people are actually using when they post about it?

Or am I completely off in the weeds and need to have my heinie spanked?

jim appleyard · Jan 22, 2007

Dave Krueger said:
... need to have my heinie spanked?

Yes, but don't call me!

Dave Krueger · Jan 22, 2007

Now I'm even more cpnfused...

I just noticed that I'm comparing apples and oranges. Some formulas use Para-Aminophenol whereas PF uses P-Aminophenol Hydrochloride. Also, the formulas I see on the web use Potassium metabisulfate where as PF uses sodium metabisulfate. So... Maybe I shoulda just bought the chemicals and mixed them according to the Darkroom Cookbook. Are any of these formulas the same as the R-09 I keep seeing?

jim appleyard · Jan 22, 2007

I've found it to be less expensive to just order Rodinal from Freestyle. It's safer as well, no mixing hydroxides and pouring drop-by-drop.

Dave Krueger · Jan 22, 2007

jim appleyard said:
I've found it to be less expensive to just order Rodinal from Freestyle. It's safer as well, no mixing hydroxides and pouring drop-by-drop.

I'm inclined to agree with you, but I didn't know about the stuff available on Freestyle when I ordered from PF.

This formula on digitaltruth that shows the concentration as being double what the formula is for the PF version.

http://www.digitaltruth.com/techdata/rodinal.php

I suppose I could assume that the PF version needs half the dillution of the Agfa version.

Neal · Jan 22, 2007

Dear Dave,

What does Photographer's Formulary have to say on the subject?

Neal Wydra

Dave Krueger · Jan 22, 2007

Neal said:
Dear Dave,

What does Photographer's Formulary have to say on the subject?

Neal Wydra

Good question. I haven't asked them yet. I've been searching through the forums and, despite the massive number of posts about Rodinal, I haven't found anything about the difference in concentration between the PF version and other formulas. Maybe the PF version just isn't used much since the pre-mixed version is still available.

I will emila PF when I get home fom work tonight.

Dave Krueger · Jan 22, 2007

Ok, I emailed PF to get the straight poop.

Using the forum search, I don't see many people posting about having used PF Rodinal successfully. If the PF says their Rodinal is substantially different than the Agfa version of Rodinal, I'll probably scrap it and just order the real thing. I also bought the PF TFX-2 to play with, so I can use that in the interim.

Neal · Jan 22, 2007

Dear Dave,

It sounds as though you have plenty to keep you busy. :>)

Neal Wydra

jim appleyard · Jan 22, 2007

Dave Krueger said:
Ok, I emailed PF to get the straight poop.

Using the forum search, I don't see many people posting about having used PF Rodinal successfully. If the PF says their Rodinal is substantially different than the Agfa version of Rodinal, I'll probably scrap it and just order the real thing. I also bought the PF TFX-2 to play with, so I can use that in the interim.

Yes, Formulary says that their Rodinal is closer to the original than the Agfa product.

Play around with it to nail the times and dilutions down. It's probably very good.

Rodinal concentration

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