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  1. #21

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    Quote Originally Posted by Muihlinn
    Check those:

    Adox APH09
    Calbe R09
    Fomadon R09
    Fomadon and Adox sell Calbe R09 under their own labels.

  2. #22
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    The best substitute for Rodinal is... well... more Rodinal. Agfa should be forced by international law to provide it to us since we have supported Agfa all these years don't you think?

    I wasn't sure if I wanted to have the spell check "learn" the words Agfa and Rodinal. I did because I might want to reminisce about the company and Rodinal from time to time in that I am not ready to let go and get over it.

    Someone should print out some Agfa Rodinal labels so we can put them on the R09 generic bottles just to make us feel better. Just a thought. Get out there and buy all of the Rodinal you can. The quicker it's off the market the better. No sense prolonging the agony. Actually, there are other developers it's not the end of the World.

  3. #23
    Muihlinn's Avatar
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    Quote Originally Posted by Gerald Koch
    Fomadon and Adox sell Calbe R09 under their own labels.
    it's the same, yes, but the distribution chain isn't the same, then perhaps someone could find useful having three brands despite it's the same product. Anyway it's also the same than agfa's, so...

  4. #24
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    Quote Originally Posted by Jurgen
    I think pat may have mis calculated the amount of hydroxide. Calculations show that your formula has 0.348 moles of paraaminophenol and 0.575 moles of sodium hydroxide. From my understanding you are to add enough hydroxide to convert the phenol into the phenolate ion. You have about 9 grams extra hydroxide which will make the pH quite high. That may explain your shorter times.

    Jurgen
    The p-aminophenol and the sulfite form a flocculent precipitate, as you know, which dissolved when I added the hydroxide. I suspect I did overdo the hydroxide, but the time for HP5+ specified for Rodinal 1+25 on the jug, 8 minutes, worked pretty well. I think part of the difference was the age of the p-aminophenol hydrochloride that I used in my first trial. I don't remember it as being coal black when I got it some years ago. When I get some more p-aminophenol I will try 14 grams instead of 23 and see what happens.

    I don't remember how I arrived at 23, but I think it was by observing how much I had to add to the solution of sodium bisulfite and p-aminophenol hydrochloride to make it work and subtract from it the amounts that would be required to make sodium sulfite and sodium chloride.

    It doesn't seem to me that 9 grams extra in the concentrate is such a terribly high concentration in the 1+50 dilution. That would be about 0.18 grams/liter, which is about 0.0045 moles. A pretty small amount of sodium bisulfite added to the working solution should neutralize that and tell me something. 0.48 grams per liter should do it.

    I don't know how to calculate the pH from the contents of the diluted solution. If the hydroxide were the only contributor, I could figure it out from the info in the CRC Handbook of Chemistry and Physics.
    Gadget Gainer

  5. #25

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    Quote Originally Posted by gainer
    Has anyone tried to concoct a developer out of Tylenol?
    You may or may not find this link interesting. While I love my photo chemicals, chemistry itself has always given me blurred vision and migraines. Fortunately my 5 year supply of Rodinal arrives tomorrow. That fact virtually assures that it will not leave the market.


    http://tinyurl.com/az3wa

  6. #26
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    You were right, Jurgen. I doctored the remains of the 500 ml I had made by adding 10 grams of sodium bisulfite to bring the pH down roughly where it would be without the extra 9 grams/liter of sodium hydroxide. The HP5+ negative at 1+25 is much better. I'll try a new batch from scratch when my supplies come in. Thanks.
    Gadget Gainer

  7. #27

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    go Patrick!!

    Mr. Gainer-please keep us updated on this. I'd rather just make it for myself. To hell with Agfa et al for the way they treat us. Once you've come up with a proper formula I can make enough for MY lifetime supply.....
    Best, Peter

  8. #28

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    I wonder how many complaints Photographer's Formulary get every year to the effect "I mixed everything in the kit but the Rodinal turned out completely black." It needs to be stressed that the developer will oxidize VERY rapidly if there is ANY excess hydroxide. By leaving a small amount of precipitate you insure that there is no excess. Think of the end point in a titration where the indicator is the precipitate.

  9. #29
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    Quote Originally Posted by Gerald Koch
    I wonder how many complaints Photographer's Formulary get every year to the effect "I mixed everything in the kit but the Rodinal turned out completely black." It needs to be stressed that the developer will oxidize VERY rapidly if there is ANY excess hydroxide. By leaving a small amount of precipitate you insure that there is no excess. Think of the end point in a titration where the indicator is the precipitate.
    Well, mine that I mixed from p-aminophenol and that had the extra 9 grams/liter, did not oxidize rapidly. OTH, the stuff I mixed from the old p-aminophenol.HCl was black as coal from the start. I seem to remember that the kit I got from the Formulary also produced very dark Rodinal from the start.

    The problem that I had with trying to leave a litle precipitate was that the reaction upon adding hydroxide solution was slow. The visual feedback was delayed enough that I added too much hydroxide. I can't quite imagine that a manufacturer mixing a large vat of Rodinal would rely on that visual feedback, especially nowadays when the purity of many of the chemicals is good enough not to depend on titration. If it is essential to leave the reaction incomplete, I think it might be better to calculate the amount of hydroxide required and subtract a little, say 1%, for good luck.

    I think I realize now that the number of molecules of hydroxide should equal the number of molecules of p-aminophenol when I use the sulfite instead of the metabisulfite. If that produces a pH that is high enough, then all the gossip about Rodinal having a lot of potasium hydroxide is just that. Why is it considered such a hazardous material for shipping? It may be because the label shows what went in, not the effective compounds that result.
    Gadget Gainer

  10. #30

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    Quote Originally Posted by gainer
    You were right, Jurgen. I doctored the remains of the 500 ml I had made by adding 10 grams of sodium bisulfite to bring the pH down roughly where it would be without the extra 9 grams/liter of sodium hydroxide. The HP5+ negative at 1+25 is much better. I'll try a new batch from scratch when my supplies come in. Thanks.
    I don't want to be critical but I did a few calculations on the rodinal formula in the darkroom cookbook. After converting the HCl salt to base and assuming all 400ml of KOH is used it appears to be about 0.5 molar in para aminophenol, about 55 grams. This would require about 20 grams of NaOH. Not sure about the sulfite.

    Also the pH of your formula at 1:25 would be about 12, at 1:50 about 11.6.

    Jurgen

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