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The wet collodion process

The wet collodion photographic process produced a glass negative and a beautifully detailed print that was preferred over earlier techniques. This method thrived from the 1850s until about 1880. Created by Getty Museum.

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  • leaf blue style avatar for user jv1022605
    How Much would they pay for the photos back then?
    (5 votes)
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  • blobby green style avatar for user Sven Loe
    Nobody should complain today about the photographic process taking too long.
    I wondered about the photographic paper though: Because the preparation of the printing paper is shown under 'light', does it just need an awful lot of time to be exposed? Or is it something about the 'sunlight' because it's explicitly mentioned?
    (3 votes)
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    • female robot grace style avatar for user Robin
      circa 1985 the lights used in a darkroom were red
      human eyes/brains are sensitive to red light and could see in there but photographic paper emulsion was made to be insensitive to it
      the photographic film (for making the negatives) was more sensitive, even to red light and could only be handled inside a cloth bag with elasticized arm holes

      apparently the technique demonstrated here used emulsion with a less sensitivity or possibly they're just acting out the steps so we can see it?

      sunlight is lots more wavelengths than light visible to humans, much more than any light bulb or flame
      http://science-edu.larc.nasa.gov/EDDOCS/Wavelengths_for_Colors.html
      (1 vote)
  • piceratops ultimate style avatar for user trek
    Are there any modern photographers who work with this technology? The images produced are quite striking and convey significant dimensionality.
    (3 votes)
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    • female robot grace style avatar for user Robin
      if a person wanted to become a modern photographer working with this technology, to learn all the steps in precise detail, there was a person named Ansel Adams who wrote a series of books entitled "The Camera," "The Negative" and "The Print" describing exactly all the hows and whys, beginning to end. they are still in print so available for reasonable prices. really good instructions with full info/specifications, measurements, and examples. the materials nowadays are easily obtained via internet, tools/work space...not sure? peak mid-20th century tech, can extrapolate backward and forward from research if master these three little books.
      (1 vote)
  • piceratops ultimate style avatar for user trek
    Why mention an unusual substance like rottenstone without an explanation? Needing to interrupt the video to look up important information like this really disruots the flow.
    (3 votes)
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  • piceratops ultimate style avatar for user trek
    After all of the care to prevent contaminants on the plate, why was the photographer not holding the plate from beneath when pouring the colloidion? Wouldn't that cause fingerprints?
    (2 votes)
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    • female robot grace style avatar for user Robin
      I was imagining a frame or a series of them, maybe a row of 5-10 to make up ahead of time? the preps could be done all in a batch and left to dry completely undisturbed then collected and packed into a satchel ready for the photo session
      also hand-held wouldn't have been perfectly level so one side of the emulsion would have been thicker (with more silver molecules) than the other
      then again...if we could find some collodion prints and look under the their mats we might see the edges all have tiny half-moons from photographer fingers

      from this demonstration I'm confused over how much of the process is the "wet" part
      (1 vote)
  • piceratops ultimate style avatar for user Dayvyd
    Around - - what is the light that is used in the dark room? How does it differ from "regular" light?
    (1 vote)
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    • aqualine tree style avatar for user jonas.reeb
      These lights are called safelights. They only emit light at wavelengths that cause little to no reaction with the photographic material (but are still part of the human visible spectrum). Which wavelengths these are depends on the material used (and I don't know the exact answer for daguerreotypes)
      (2 votes)
  • aqualine ultimate style avatar for user Gabrielle Pantano
    What type of light are they using in the dark room, it kind of looks like natural light, but wouldn't that ruin the process? Also how do the photographers know how long to expose the plate during taking the picture when they can't see what the plate looks like, since the amount of light would vary per picture, thus changing the exposure time, did they just learn from practice?
    (1 vote)
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  • aqualine ultimate style avatar for user Gabrielle Pantano
    At does any one know what those gigantic chains behind the man were used for? Also does any one know if the chemicals being mixed and poured before the silver nitrate gets added had to be in a darkroom while being handled or was it just after the silver nitrate came into the process?
    (1 vote)
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Video transcript

- [voiceover] In 1851 the Englishman Frederick Scott Archer invented the wet collodion process of making negatives. This process allowed photographers to produce finely detailed images on paper and to print an unlimited number of copies. These key features were improvements over the previous two photograph processes, the daguerreotype and the calotype. From 1851 until about 1880 the wet collodion process became the dominate method for making photographs throughout Europe and North America. Producing a wet collodion image had to be done quickly and efficiently. This is because collodion, the main chemical used, will dry up and lose its sensitivity after about 10 minutes. Photographers used portable darkrooms, so the plate could be developed immediately after it was shot. The wet collodion process can be broken down into a number of equally critical steps. First the edges of the glass plate are smoothed with a sharpening stone to help the collodion adhere better to the plate. The glass is polished with a solvent, such as rotten stone or glass wax. Next the glass is carefully cleaned again to remove any dust particles. This is important because any remaining particles will show up as dark spots on the final image. A mixture of iodides, bromides, ether, and alcohol are added to the collodion to help make it photosensitive. The solution is then allowed to age for (mumbling) a week prior to use. Using a method called flowing the plate, the collodion is poured carefully onto the center of the glass. The collodion enables the silver nitrate to adhere to the plate, so it is crucial that the collodion covers the entire surface. Inside the darkroom the photographer dips the plate into a bath containing silver nitrate, the chemical that will make the plate sensitive to light. The plate is left in the bath for about three to five minutes. The photographer then removes the sensitized plate from the silver bath and lays it inside the plate holder. The collodion side is placed face down so that it can receive the path of light once inside the camera. Any excess silver nitrate is removed from the back. Once closed the plate holder emits no light, which allows it to be safely removed from the darkroom. in the back of the camera the photographer makes final adjustments to the composition to the image before inserting the plate holder. He must make any changes now, for once the holder is in place it is no longer possible to focus the camera. The plate is exposed to light by first pulling the dark slide out and then removing the lens cap to expose the plate for the required amount of time. The lens cap is then placed over the lens and the dark slide inserted back in the plate holder. Once closed, the plate holder is removed from the camera and brought back into the darkroom. In the darkroom the glass plate is removed from the plate holder. Developer is then poured onto the plate. It is important that the developer is poured in an even, sweeping motion, otherwise it will leave ridges and markings on the final image. When the photographer is satisfied with the image, water is poured over the plate to stop the development. The exposed and developed plate is placed in a bath of fixer to permanently preserve the image. The plate is left in the fixer until it clears. After removal the plate is washed thoroughly in water. After the plate is dry it has to be varnished to protest the fragile image surface from damage. The plate is heated to facilitate this process. A clear coat of varnish is applied to the plate, much as the collodion was. This must be done very carefully, since the varnish can accidentally dissolve the image. Once the plate is varnished a print can safely be made from it. Photographers most commonly printed wet collodion negatives on albumen paper. This is made by first floating a sheet of photographic paper on a solution made from egg whites, then floating it in a tray of silver nitrate. After drying, the paper is placed in contact with the negative in a printing frame. The negative is then exposed to sunlight and the image emerges during the exposure. The photographer watches it carefully to determine when to arrest exposure. The finished print is called an albumen print. Colors range from reddish to purplish-brown and the prints have a lush, glossy surface. Albumen prints made from wet collodion negatives remained extremely popular until about 1880 when they were replaced by more industrialized photographic methods.