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Rodinal failure

Not necessary Richard, MSDS are slightly different.
Click to expand...

Reading MSDSs can be difficult. Remember that manufacturers really don't want people to know what is in their proprietary formulas. They often resort to perfectly legal misdirection. For example hydroquinone can be called 4-hydroxyphenol or pap as either a substituted amine OR a substituted phenol. There are naming conventions in organic chemistry to prevent this but manufacturers seldom follow them. There are also various other subterfuges that can be used.
 
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True, the key is Section 9.
 
I believe that when all the sulfite in Rodinal or variations is used up the p-aminophenolate left will oxidize.
There is a lot of sulfite in Rodinal and the p-aminophenolate does not hydrolyse, that is why it lasts so long.
I'm not convinced that any variation contains a compound that can inhibit oxidation of the bulk solution.
Therefore I favour the porosity of containers explanation.
 
Rodinal is merely a concentrated paraaminophenol developer.
In films hayday many people sold clones that lasted as well.
I've had a near empty bottle of Azol ok after a decade.
I've also forgotten to replace the cap on my current bottle!
Not had any failures with any of the clones.
You can get a lotta crystals cause the solution can be saturated.
I've mixed it from scratch. You need a full face visor.
Could be operator error?
 
[QUOTE="Xmas, post: 1756456, member: 15409"

Could be operator error?[/QUOTE]

Doubtful. While I'm far from perfect, I'm a very careful darkroom user and I've been doing films in Rodinal for decades and have had no failure until recently. Real Rodinal from Agfa lasted forever and I once got ahold of a old glass bottle with the cork that was half-full. It was fine.

Now my APH09 lasts only a few months and it happens to all the films I dev in it and over the course of 3-4 bottles.

Blast Agfa anyway for going out of business!
 
jim appleyard said:
[QUOTE="Xmas, post: 1756456, member: 15409"

Could be operator error?
Click to expand...

Doubtful. While I'm far from perfect, I'm a very careful darkroom user and I've been doing films in Rodinal for decades and have had no failure until recently. Real Rodinal from Agfa lasted forever and I once got ahold of a old glass bottle with the cork that was half-full. It was fine.

Now my APH09 lasts only a few months and it happens to all the films I dev in it and over the course of 3-4 bottles.

Blast Agfa anyway for going out of business![/QUOTE]


Jim,
What is a person suppose to buy that is the closest to good old Agfa Rodinal?????
 


Jim,
What is a person suppose to buy that is the closest to good old Agfa Rodinal?????[/QUOTE]
I'm the most carefree (careless) worker and I've not had any problems (yet).
You can scratch mix up a
published recipe or PA Rodinal Jay (zorkicat) had a bottle from '05 that was still good. If you are confident with drain cleaner.
 


Jim,
What is a person suppose to buy that is the closest to good old Agfa Rodinal?????[/QUOTE]

Yeah, mix your own, but I tried this one and din't have good luck. It's an option, but I'd have to re-test all my times and would rather not do that.

Previous posts have suggested to try Adox Rodinal and NOT the APH09 that I've been using. Both are available from Freestyle, APH09 is the cheaper of the two.
 
jim appleyard said:
Jim,
What is a person suppose to buy that is the closest to good old Agfa Rodinal?????
Click to expand...

Yeah, mix your own, but I tried this one and din't have good luck. It's an option, but I'd have to re-test all my times and would rather not do that.

Previous posts have suggested to try Adox Rodinal and NOT the APH09 that I've been using. Both are available from Freestyle, APH09 is the cheaper of the two.[/QUOTE]
Try
(there was a url link here which no longer exists)
Zorkicat did long term tests +5 years in plastic with his.
His site has been down a while now.
 
Try
(there was a url link here which no longer exists)
Zorkicat did long term tests +5 years in plastic with his.
His site has been down a while now.[/QUOTE]


Just for informational purposes, attached is the MSDS for Agfa Rodinal from year 1999. You will notice the current offering MSDS is similar in the two primary constituents, but what seems to be missing is the potassium sulfite which is the preservative. Older versions indicate the use of potassium metabisufite as the preservative. Since the current links to MSDS sheets make no mention of a preservative, although one assumes there must be some, thiat may account for the poor keeping quality being experienced.
 

Attachments

  • AGFA Rodinal MSDS.pdf
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There are three ways to arrive at the same rodinal concentrate. You can start with potassium sulfite, potassium bisulfite, or potassium metabisulfite. You start with an amount of hydroxide needed to create the phenolate salt of paraminophenol. Then each sulfite requires a different amount of potassium hydroxide but the end product is always the same.

If you want real rodinal then you cannot use drain clearer (lye). The potassium compounds are more active photographically than their sodium equivalents. So stick with the potassium ones across the board. For reasons I have never been able to figure out the potassium salts are cheaper and easier to obtain in Europe. That is why I have never been particularly fond of the homebrew versions made here in the US. Last I looked potassium hydroxide was available from The Chemistry Store. http://www.chemistrystore.com/

There are quite a few rodinal-like developer formulas. But they all have basically the same formula. Per liter of concentrate they contain the equivalent of 50 g of paraminophenol base. For a good recipe follow the following link.

(there was a url link here which no longer exists)
 
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