Page 1 of 2 12 LastLast
Results 1 to 10 of 18

Thread: Homemade emulsion help please

  1. #1

    Join Date
    Dec 2020
    Location
    Snohomish, Washington, USA
    Posts
    5

    Homemade emulsion help please

    I've been really enjoying the DIY aspect of large format and the wet darkroom. With that in mind, attempting salt and/or albumen printing strikes me as the next logical step.

    In mixing up the silver nitrate solution, there was a problem. Cutting to the end result, it turned into a pasty liquid, looking somewhat like thin Elmer's glue. I do not have tools to measure pH or specific gravity.

    Here's what I did:
    1) Dissolve 12 g silver nitrate into 50 ml of distilled water - no apparent trouble
    2) Dissolve 6 g citric acid into 50 ml of distilled water - no apparent trouble
    3) Pour the citric acid into the silver nitrate and swirl to mix - Immediate milky appearance and thickening!

    It is my understanding that it should have stayed clear. All tools and containers were clean before starting, and only the correct chemicals were in the room at the time. (Nothing got inadvertently switched.) Everything was measured carefully. My scale has always been reliable.

    I fully expect the suggestion that something wasn't as clean as I had thought. That's plausible and supported by the evidence but since I believed it was all clean and well-rinsed, I wouldn't know what to suspect as a contaminant.

    So the questions are:
    - Any ideas what might have gone wrong? If I try again, I'd prefer success.
    - Might there be a way to rescue the solution? AgNO3 is expensive...
    - Or maybe just ignore it and it'll be fine? I have doubts but if the experts agree...?

    I have tried searching the forum but haven't found an answer yet. Thanks for all the answers on other topics that I have found!

    - Anthony

  2. #2
    Tin Can's Avatar
    Join Date
    Dec 2011
    Posts
    22,319

    Re: Homemade emulsion help please

    Go look at https://www.timlaytonfineart.com/blog

    There are others to find
    Tin Can

  3. #3

    Join Date
    Dec 2020
    Location
    Snohomish, Washington, USA
    Posts
    5

    Re: Homemade emulsion help please

    That's gold, thank you!

    I've only been in this side of things about a year but hadn't found this resource yet.

    Much appreciated.

  4. #4
    Tin Can's Avatar
    Join Date
    Dec 2011
    Posts
    22,319

    Re: Homemade emulsion help please

    Tin Can

  5. #5
    Tin Can's Avatar
    Join Date
    Dec 2011
    Posts
    22,319

    Re: Homemade emulsion help please

    Tin Can

  6. #6

    Join Date
    Jun 2017
    Location
    West Coast
    Posts
    2,121

    Re: Homemade emulsion help please

    Quote Originally Posted by Anthony O View Post
    I've been really enjoying the DIY aspect of large format and the wet darkroom. With that in mind, attempting salt and/or albumen printing strikes me as the next logical step.

    In mixing up the silver nitrate solution, there was a problem. Cutting to the end result, it turned into a pasty liquid, looking somewhat like thin Elmer's glue. I do not have tools to measure pH or specific gravity.

    Here's what I did:
    1) Dissolve 12 g silver nitrate into 50 ml of distilled water - no apparent trouble
    2) Dissolve 6 g citric acid into 50 ml of distilled water - no apparent trouble
    3) Pour the citric acid into the silver nitrate and swirl to mix - Immediate milky appearance and thickening!

    It is my understanding that it should have stayed clear. All tools and containers were clean before starting, and only the correct chemicals were in the room at the time. (Nothing got inadvertently switched.) Everything was measured carefully. My scale has always been reliable.

    I fully expect the suggestion that something wasn't as clean as I had thought. That's plausible and supported by the evidence but since I believed it was all clean and well-rinsed, I wouldn't know what to suspect as a contaminant.

    So the questions are:
    - Any ideas what might have gone wrong? If I try again, I'd prefer success.
    - Might there be a way to rescue the solution? AgNO3 is expensive...
    - Or maybe just ignore it and it'll be fine? I have doubts but if the experts agree...?

    I have tried searching the forum but haven't found an answer yet. Thanks for all the answers on other topics that I have found!

    - Anthony
    Hi Anthony.
    That recipe for salted paper sensitizer is very similar to many variations of the recipe, so the proportions and method is correct. However, I do NOT use the Citric acid in making my AgNO3 sensitizer - you really don't need it unless you plan to keep the sensitized, dried paper for more than 24 hours before using.

    So, that leads me to think there is a contamination problem. Are you 100% certain that what you have used is pure Citric acid, with no other additives?
    Can your silver nitrate be saved? That's a good question. Without knowing why the solution went "pasty", the remedy is uncertain. At least it was only 12 grams of AgNO3 and not 120!

  7. #7
    Tin Can's Avatar
    Join Date
    Dec 2011
    Posts
    22,319

    Re: Homemade emulsion help please

    Tin Can

  8. #8

    Join Date
    Jun 2017
    Location
    West Coast
    Posts
    2,121

    Re: Homemade emulsion help please

    Randy, this link, and the next one on YouTube are about making film type emulsions from scratch. Anthony is looking for a recipe for sensitizing Salt and/or Albumen paper. (Unless I have completely misinterpreted his post)

  9. #9

    Join Date
    Dec 2020
    Location
    Snohomish, Washington, USA
    Posts
    5

    Re: Homemade emulsion help please

    I had thought that the nitrate keeps better with the addition of citric acid. But if that's only after it's coated onto paper, I'd just as soon leave it out! I hadn't planned to keep coated papers much longer than it takes them to dry.

    Said acid I purchased from Photographer's Formulary a couple months ago, this was the first time I had opened the can. The nitrate was also a recent purchase from Bostick & Sullivan, also previously unopened.

    My strongest suspect is the bottle used for the final mix. It's a 4-oz (118 ml) brown glass bottle that formerly held vanilla. Washing was by vigorously shaking with dish soap inside, then rinsing. So if that was inadequate, the contaminant would be either some tiny bit of vanilla from the cap, or the soap but I thought I had rinsed really well afterwards. I obviously missed something, else it wouldn't have gone wonky.

    Thanks!

  10. #10

    Join Date
    Jun 2017
    Location
    West Coast
    Posts
    2,121

    Re: Homemade emulsion help please

    Quote Originally Posted by Anthony O View Post
    I had thought that the nitrate keeps better with the addition of citric acid. But if that's only after it's coated onto paper, I'd just as soon leave it out! I hadn't planned to keep coated papers much longer than it takes them to dry.

    Said acid I purchased from Photographer's Formulary a couple months ago, this was the first time I had opened the can. The nitrate was also a recent purchase from Bostick & Sullivan, also previously unopened.

    My strongest suspect is the bottle used for the final mix. It's a 4-oz (118 ml) brown glass bottle that formerly held vanilla. Washing was by vigorously shaking with dish soap inside, then rinsing. So if that was inadequate, the contaminant would be either some tiny bit of vanilla from the cap, or the soap but I thought I had rinsed really well afterwards. I obviously missed something, else it wouldn't have gone wonky.

    Thanks!
    Hi Anthony.
    The point of adding Citric acid to the AgNO3 solution is as a preservative once its been applied to the salted paper. There is no absolute requirement for adding the acid to the silver solution, especially if you plan to expose sensitized paper immediately after drying. (that's what I do.)
    I would appear that you have the correct chemicals, having bought from two photography sources. However, one thing I have discovered is that sometimes Photographers Formulary chemistry has sat around a long time before being sold, and I've found that some materials go stale by the time I got them. But it sounds like you bought it from PF directly, so that seems unlikely.
    How sure are you that your distilled water is really distilled water (no minerals)? Sometimes there are brands labeled as "distilled" water that are actually just deionized/demineralized if you look closely at the label. Minerals in the water can ruin a silver solution.
    My only other suggestion would be contamination from the bottle you used. Reusing glassware that has previously been used for food substances is a gamble, no matter how well you rinse it out. Its better to buy new glassware specifically for each chemical and never use it for anything else, especially when making up solutions with Silver nitrate. Still, it seems odd that a tiny bit of vanilla contamination would result in the solution immediately turning to paste.

    My suggestion is to start again, and omit the Citric acid.

Similar Threads

  1. Replies: 6
    Last Post: 28-Sep-2014, 12:45
  2. Fuji Instant Emulsion Lifts and Emulsion Transfers
    By Dirk Rösler in forum Resources
    Replies: 7
    Last Post: 25-Mar-2013, 19:41
  3. Tray Processing Tip: Don't Mix Emulsion Up and Emulsion Down
    By Bill Burk in forum Darkroom: Film, Processing & Printing
    Replies: 8
    Last Post: 22-Jun-2012, 19:10
  4. emulsion up or emulsion down? (4x5 in trays)
    By BetterSense in forum Darkroom: Film, Processing & Printing
    Replies: 23
    Last Post: 14-Jan-2011, 06:21
  5. homemade shutter (BIG)..
    By Emil Schildt in forum Lenses & Lens Accessories
    Replies: 5
    Last Post: 10-May-2010, 01:45

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •