New Rodinal formula on Digitaltruth.com
Has anyone mixed and developed a film in the recently corrected Rodinal formula on the digitaltruth film developer page.
It has been posted for about 9 days now which should be enough time to have used the developer given the standing times during filtration (4 days).
I would appreciate knowing what results anyone has had (compared to previous Rodinal brews) before I commit to mixing a batch myself due to having had to throw away a failed batch using old formula.
I rather suspect the author is the same gentleman whose recent threads on developer formulae here disappeared amidst a welter of debate about inaccuracy ...
I have seen this (I think) A couple of days ago I went to check the times for developing Kentmere 100 at half the stated ISO setting and was surprised to note that since my last visit a lot of information about Kentmere films has dissapeared. There is now only one guide for 100 ISO film and that is at 50 ISO at 1-50 dilution as I wanted and none for the standard 100 ISO. There were two however using the 400ISO version.
It's not close to Rodinal, first it uses p-Aminophenol Hydrochloride and has far to little Potassium Metabisulphite.
Secondly in the article KennyE has written he correctly gives an early p-Aminiphenol formula but very incorrectly calls it Rodinal. There's plenty of agfa literature to show this is more of KennyE's fiction:
At NO stage has Rodinal ever contained Carbonate.
Last edited by Ian Grant; 07-22-2013 at 06:18 AM. Click to view previous post history.
Ian are you still planning to publish your "Complete guide ..." ?
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Yes, but it's complex and hasn't progressed as fast as I'd planned.
Originally Posted by pdeeh
Ok thanks, what I think I'll do is make a batch of Rodinal as previously posted and see how that goes as below:
EZ Rodinal New (Calbe R09 substitute)
To 800 ml water, add:
p-Aminophenol base 50 g
Potassium sulphite (anhyd) 300 g
Potassium hydroxide 24 g
Potassium Bromide 0.8 g
Benzotriazole 1% 10 ml
Water to make 1 litre
Is it OK to desolve the Benzotriazole in methanol to make the 1% solution and is the working solution still 1 +25 , 1 +50 etc with appropriate dev times as published by Agfa Rodinal? I have 4-aminophenol hydrochloride just recieved from Silverprint.
Your advice would be very much appreciated
George, I missed a step in that formulae, ideally you need to generate the Potassium Sulphite from Potassium Metabisulphite and Potassium Hydroxide, that's the only way you'll get that amount of sulphite in solution easily.
Ok thanks I will try that, I will need to read up on how to do that first before I actually start mixing the chemicals.
here is a formulation for Rodinal concentrate which goes back to the formula of Agfa which was discovered by allied troups after WW2:
Solution 1.) To 650 ml potassiumsulfite-solution 45 % (e.g. from BASF) add 55 g p-aminophenol (free base). It does not dissolve.
Solution 2.) 200 ml deion. water + 40 g EDTANa4 + 42 g potassiumhydroxide (caution, gets hot!) + 15 g potassiumbromide
After all components are dissolved, add to solution 1.) and fill up with deion. water to 1000 ml.
In the original formula there was no EDTANa4 and a special antifog (anthraquinonetriazole) which is no longer available; therefore KBr is added.