Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 68,713   Posts: 1,483,018   Online: 678
      
Page 2 of 2 FirstFirst 12
Results 11 to 19 of 19
  1. #11
    Tom1956's Avatar
    Join Date
    May 2013
    Location
    US
    Shooter
    Large Format
    Posts
    1,688
    Glacial mixes 3:8 to get 28%. Then use 6 oz 28% to the gallon of water. That simple.

  2. #12
    Nicholas Lindan's Avatar
    Join Date
    Sep 2006
    Location
    Cleveland, Ohio USA
    Shooter
    Multi Format
    Posts
    2,372
    Images
    4
    Quote Originally Posted by Nicholas Lindan View Post
    I use a combination of Kodak Indicator Stop bath and 28%: 33ml of 28% + 6ml of indicator -> 1 liter of working strength.
    The above mixture proportions take into account the differing acid concentrations of the two.
    DARKROOM AUTOMATION
    f-Stop Timers - Enlarging Meters
    http://www.darkroomautomation.com/da-main.htm

  3. #13

    Join Date
    Jul 2010
    Location
    Southern USA
    Shooter
    Multi Format
    Posts
    3,531
    Quote Originally Posted by Tom1956 View Post
    Glacial mixes 3:8 to get 28%. Then use 6 oz 28% to the gallon of water. That simple.
    May I add that when diluting concentrated acids always add the acid to the water never the other way around
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  4. #14

    Join Date
    Jul 2005
    Shooter
    Multi Format
    Posts
    148
    Why not use citric acid? It has no odor, easy to mix, and is very inexpensive.

    Thomas
    Thomas

    No art passes our conscience in the way that film does, and goes directly to our feelings, deep down into the dark rooms of our souls.
    — Ingmar Bergman

  5. #15
    Athiril's Avatar
    Join Date
    Feb 2009
    Location
    Melbourne, Vic, Australia
    Shooter
    Medium Format
    Posts
    2,467
    Images
    28
    Quote Originally Posted by Gerald C Koch View Post
    The problem in the original question is that the strengths of glacial acetic acid and Kodak Indicator Stopbath are different. Mixing them together would create a solution of unknown strength. Better to use each alone until one is used up.
    The indicator will still indicate at the pH change.


    You can always just dilute the stop bath as normal, and add a small volume of glacial acetic acid to this when the pH indicator indicates it's bad, thus lowering the pH again the indicator will switch back to the normal colour.

  6. #16

    Join Date
    Jul 2010
    Location
    Southern USA
    Shooter
    Multi Format
    Posts
    3,531
    I have never really seen the need for indicating stop baths. I never attempt to save used stop bath and my feet usually give out before the stop bath does.

    In addition acetic acid has its own built in indicator that is its smell. When the bath no longer smells like acetic acid it should be discarded. Easy and simple.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  7. #17

    Join Date
    Dec 2007
    Location
    Seattle, Washington area
    Shooter
    Large Format
    Posts
    365
    Quote Originally Posted by Gerald C Koch View Post
    May I add that when diluting concentrated acids always add the acid to the water never the other way around
    My high school chem teacher told us an easy way to remember that sequence. She said acid > water is "aw wight."

  8. #18
    KennyMark's Avatar
    Join Date
    Jun 2013
    Location
    Holland, MI
    Shooter
    Multi Format
    Posts
    147
    Quote Originally Posted by silveror0 View Post
    My high school chem teacher told us an easy way to remember that sequence. She said acid > water is "aw wight."

    Mine taught us "Do as you oughta, add acid to watah". The efficacy of mnemonic devices is proven daily.
    If you call it a "prime lens" because it's a fixed-focal length (i.e. not a zoom lens), then as Inigo Montoya said so eloquently, "You keep using that word. I do not think it means what you think it means."

  9. #19
    erikg's Avatar
    Join Date
    Feb 2003
    Location
    pawtucket rhode island usa
    Shooter
    Multi Format
    Posts
    1,356
    Quote Originally Posted by KennyMark View Post
    Mine taught us "Do as you oughta, add acid to watah". The efficacy of mnemonic devices is proven daily.
    Great! With a Rhode Island accent even. That's wicked smaht.

Page 2 of 2 FirstFirst 12


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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