Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,300   Posts: 1,536,028   Online: 1037
      
Results 1 to 8 of 8
  1. #1

    Join Date
    Jan 2005
    Location
    Italy
    Shooter
    Multi Format
    Posts
    232

    Alternative to Gallic Acid in calotype negative process

    Hello there,

    after printing saltprints for a while I want now to try the rest of the original process which included the making of a "calotype" negative in camera.

    I have a 4x5" camera and all the ingredients except the gallic acid. I don't think I can find it close to where I live, I'll have to order it somewhere else, spending also for shipping etc...

    As I have a large assortment of raw chemicals now... I was wondering if I could use an alternative to it. For example, gallic acid is indicated as an alternative to tannic acid for cyanotype toning... Among other acids is there anything that could replace the gallic acid in calotype negatives making? Before doing anything I'd like to ask expert chemists :-) on the forum.

    tia

  2. #2

    Join Date
    Oct 2005
    Location
    Pakistan
    Shooter
    Multi Format
    Posts
    266
    I thought somebody else with more knowledge would jump in...
    I ordered gallic acid from a store which supplies teaching materials for schools, also for chemical experiments. You might try to locate such a store in the area where you live.
    I suppose you read Alan Greene's book?
    I once tried gallic acid as a developer for prints (not negatives!), but my experiments came to naught, and I left them there, getting interested in other processes.
    My best advice is: don't try to get around this one ingredient. Such old recipies are generally difficult enough to bring to life, and trying to substitute one ingredient for another is likely to make your experiments very frustrating.

    By the way, should you succeed with your endeavour, i'd like to see a print...

  3. #3

    Join Date
    Jan 2005
    Location
    Italy
    Shooter
    Multi Format
    Posts
    232
    Quote Originally Posted by Lukas Werth
    I thought somebody else with more knowledge would jump in...
    I ordered gallic acid from a store which supplies teaching materials for schools, also for chemical experiments. You might try to locate such a store in the area where you live.
    I suppose you read Alan Greene's book?
    I once tried gallic acid as a developer for prints (not negatives!), but my experiments came to naught, and I left them there, getting interested in other processes.
    My best advice is: don't try to get around this one ingredient. Such old recipies are generally difficult enough to bring to life, and trying to substitute one ingredient for another is likely to make your experiments very frustrating.

    By the way, should you succeed with your endeavour, i'd like to see a print...

    ok... I'll go for the gallic acid... Too bad because I had potassium iodide and silver nitrate, among other things. The fact is, in short: I live in Italy, in a not so large city... This kind of "historical photography" is unknown by the majority of the people (everyone went digital but that didn't set a real difference - photo was underrated anyway). The photo shops almost ceased to sell bw chemicals as well. I don't care about these issues because I mix my own stuff and know were to buy raw chemicals online in a store located 500km from my home. But this store doesn't have gallic acid for some reason... So I have to order stuff from another company in Milan. Which is by the way cheaper, but you have to buy larger amount of chemicals (usually min 1kg which is not always needed). Maybe I'll do that and add some sodium thyosulfate, I'm running out of it... In the beginning I wasn't using that for fixing saltprints, but in the end I found that it delivers a better tone than standard fixers (diluted or exahusted). Do you fix calotype negatives in hypo? Is there any difference if you fix them in regular diluted fix?

    thanks

  4. #4

    Join Date
    Oct 2005
    Location
    Pakistan
    Shooter
    Multi Format
    Posts
    266
    Quote Originally Posted by Fulvio
    Do you fix calotype negatives in hypo? Is there any difference if you fix them in regular diluted fix?

    thanks
    Well, salt prints... no, I take normal rapid fixer which I neutralize by adding sodium carbonate. I have never noticed any disadvantage. Neutralizing it is necessary, though - and dilution, of course!

  5. #5

    Join Date
    Jan 2005
    Location
    Italy
    Shooter
    Multi Format
    Posts
    232
    Quote Originally Posted by Lukas Werth
    Well, salt prints... no, I take normal rapid fixer which I neutralize by adding sodium carbonate. I have never noticed any disadvantage. Neutralizing it is necessary, though - and dilution, of course!

    That's strange. I never added anything to the fixer...

    The fixer "bleaches" the print, but then when it dries and oxidizes to the air gains contrast again.

    I use some exhausted fixer from my bw silver printing (agfa)... Maybe diluted even more. But I never added sodium carbonate (I have the chemical which I use as a bleach for cyanotypes among other things)... Nevertheless the prints look fine. I like the ones in sodium thyosulfate more... They're more brownish/sepia in tones. The ones fixed in Agefix are more purplish and I don't like them too much. I also tried to correct the tone with a sulphide toner without pleasing results (it flattens way too much the contrast). Didn't try other toners (I have here a blue toner and a red copper toner - I guess they won't work though).


    I also noticed that brown tone is more likely to come out if I use marine salt instead of ammonium chloride (but the difference is small, the latter delivers a slightly higher contrast but just slightly).

    What I was looking for was a POP-like image (dunno if you ever tried those from kentmere)... But saltprint is different, yet nice anyway.

  6. #6
    Christopher Nisperos's Avatar
    Join Date
    Oct 2004
    Shooter
    Multi Format
    Posts
    380
    Quote Originally Posted by Fulvio
    ok... I'll go for the gallic acid... I live in Italy, in a not so large city...The photo shops almost ceased to sell bw chemicals ... I mix my own stuff and know were to buy raw chemicals online in a store located 500km from my home. But this store doesn't have gallic acid for some reason... So I have to order stuff from another company in Milan. Which is by the way cheaper, but you have to buy larger amount of chemicals (usually min 1kg which is not always needed).
    thanks
    Ciao Fulvio!

    Try Wolfgang Moersch, (http://www.moersch-photochemie.de/) Good guy, fair prices, plus he's a chemist and a printer ... he may be able to help you on small quantities. His English is so-so, but maybe Lukas (Werth) could help?

    Also, I would recommend calling Mirko, the owner of FotoImpex in Berlin. If he can't help you, he'll know who can. (attention! he's probably a little busy at the moment, preparing for photokina!)

    Good luck!

    Christopher
    Paris
    .

  7. #7

    Join Date
    Oct 2005
    Location
    Pakistan
    Shooter
    Multi Format
    Posts
    266
    Quote Originally Posted by Christopher Nisperos
    maybe Lukas (Werth) could help?
    I am ready to help, but will be away from my desk during the coming week.

    About adding an alkali to the fixer: this is of course not necessary with plain hypo, but those "rapid fixers" available (I get mine from Impex) are very acidic, and this bleaches salt prints, kallitypes and thelikes very much. It is also just what you don't want with staining developers, so neutralizing the fixer is strongly recommended. It is also easier washed out this way.

  8. #8

    Join Date
    Jan 2005
    Location
    Italy
    Shooter
    Multi Format
    Posts
    232
    It's alright, thanks for the hints about chemistry shopping. But I will buy some in Italy later, I can't find them in my city but it's ok to buy somewhere else in my own country, it's better.

    bye



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin