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  1. #1
    BetterSense's Avatar
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    Easiest emulsion/chemisty

    So, I'm not a historian, but I understand that there were multiple technologies available before silver gelatine took over in the 20th century. There was gum bichromate and dagurrotype and probably others.

    I was reading the silver gelatine emulsion making forum and it looks fun, but it looks hard.

    After the zombie apocalypse, industry as we know it will not exist, so photography will have to be something pre-industrial. What is the easiest chemistry, period? Requirements are a long life (decades or centuries). Did technologies develop roughly from simple to complex and from easy to hard? Now, knowing the history, what is the easiest way to get a fixed image using the simplest equipment?
    f/22 and be there.

  2. #2
    Dr Croubie's Avatar
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    If we're talking Post-Zombie-Apocalypse, then there's not many chemicals that will be easy to get.

    How about the Albumen process? As long as Zombies don't develop a taste for chickens then there'll always be eggs around to use...

    ps, for a quick-read history, try this.
    An awful lot of electrons were terribly inconvenienced in the making of this post.

  3. #3
    Hexavalent's Avatar
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    As noted, in a post-zombie apocalypse (PZA) scenario, chemicals and equipment will likely be scarce.
    This leaves us with what can be scrounged or easily (relatively) made.

    For prints: salted-paper and its variants (albumen, casein etc.,), cyanotype, VDB are all very DIY and do not demand super high-purity materials.

    Camera negatives: Collodion would be hard to find/make, but a slow ortho silver-gelatin emulsion could be made without fancy equipment or exotic chemistry. It doesn't even have to be coated on glass or film (paper works), and gelatin can be replaced by other colloids. Easy - yes! Fast with latitude - No!


    Making a slow but usable silver-gelatin emulsion is NOT difficult. Making a faster emulsion requires a bit more precision and technique.
    Further increasing speed, controlling the curve shape, adding spectral sensitivity, latitude, acutance, anti-halation, etc., etc., each add complexity, demand high-quality ingredients, and demand precise methods.

    Just in case, you might want to stash a few boxes of film and some developer before the zombies arrive.
    - Ian

  4. #4
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    here (in my opinion - it gotta be easy for me to do it...)

    Ok - I am a total amateur when it comes to making my own liquid emulsion.. but I think more should try it out.. so here's the recipe (from the book Silver Gelatin) and a few observations so far...

    A:
    Gelatin (food gelatin) 20g
    Potassium bromide : 16g
    Distilled water 125ml
    Add the gelatin to the water and allow to swell.
    Raise the temperature to 50deg. C (water jacket)
    Add the Potassium Bromide and stir to all is dissolved.
    B:
    Silver Nitrate: 20g
    Distilled water 125ml
    Raise the temperature of B to 40 degrees – go to the darkroom and mix the two solutions.
    Small quantities at a time while stirring.
    Finally filter it through a cotton wool or similar..
    Ready to use.

    Observations:
    I first applied one layer of gelatin (it seems to melt at a lower degree than I am used to).
    Too grey (looks mottled/spottet and with no blacks)
    Then two layers: better, but I realized I should give it a third layer (maybe if the temp was a little lower, the gelatin wouldn’t be as liquid and therefore would not be so thin? Time will tell)
    I tried the normal way: making test prints – let it soak in the developer for about 2min…= bad idea..
    Grey and spots all over the place – especially in the highlights…
    So at the brink of total frustration with only two pieces of paper left, I thought : ”Fu*k it – I’ll try something I normally would never do:
    Full aperture – about 30-40 seconds of exposure – a fresh developer at double strength than normal – and then only 10-15 sec development…
    Interesting! The image looked grey/flat, but after rinsing and when put in the fix, the fix cleared the image; the blacks became more black and the final image turned out fine!
    When dry with a beautiful warm, almost brown hue to it…

  5. #5

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    Very interesting, gandolfi! Can you point to the images?

  6. #6
    gandolfi's Avatar
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    Quote Originally Posted by mkillmer View Post
    Very interesting, gandolfi! Can you point to the images?
    I can...
    Attached Thumbnails Attached Thumbnails kristina.jpg   monika.jpg  

  7. #7
    Mainecoonmaniac's Avatar
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    Take a look here.

    http://thelightfarm.com/
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
    Aaron Chang



 

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