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Thread: The Uranotype Thread

  1. #31

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    Re: The Uranotype Thread

    Are you sure a Geiger counter will pick up alpha radiation? I thought that angeoger counter had a window in front of the detector which would stop alpha which is why we used scintillation cocktail fluid and read alphas indirectly as light flashes in a specialized counter. I could be wrong it's been a long time. Also, there are many isotopes of U. I doubt the highly energeticly emitting ones are sold for photography. In other words, they might be alpha emitters not beta or gamma and if so, the Geiger counter might not find them.

  2. #32
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    Re: The Uranotype Thread

    Hi Fr. Mark,

    Not all counters will detect alpha particles but some will: https://www.amazon.com/exec/obidos/A...re-bullets-btf. Unlike beta and gamma particles, alpha, which are helium nuclei, are rather heavy and only are only able to travel a few centimeters in air so you have to have your detector up close to the sample to detect it. I am toying with purchasing one of these https://www.amazon.com/RADEX-RD1503-...6CKY6Y23GMGJ11 to play with measuring seawater, soil...and my uranotypes of course. (I believe this was the make of the counter on the PBS program.)

    During the first half of the 19th century, many photosensitive metal salts had been identified as candidates for photographic processes, among them uranyl nitrate. The prints thus produced were alternately referred to as uranium prints, urbanities, or more commonly uranotypes. The first uranium printing processes were invented by a Scotsman, J. Charles Burnett, between 1855 and 1857, and used this compound as the sensitive salt. Burnett, authored an 1858 article comparing "Printing by the Salts of the Uranic and Ferric Oxides" The basis for the process lies in the ability of the uranyl ion to pick up two electrons and reduce to the lower oxidation state of uranium(IV) under ultraviolet light. Uranotypes can vary from print to print from a more neutral, brown russet to strong Bartolozzi red, with a very long tone grade. Surviving prints are slightly radioactive, a property which serves as a means of non-destructively identifying them. Several other more elaborate photographic processes employing the compound sprung up and vanished throughout the second half of the century with names like Wothlytype, Mercuro-Uranotype and the Auro-Uranium process. Uranium papers were manufactured commercially at least until the end of the 19th century, vanishing in the face of the superior sensitivity and practical advantages of the silver halides. Nevertheless between the 1930s through the 1950s Kodak Books still described a uranium toner (Kodak T-9) using uranium nitrate hexahydrate. Some alternative process photographers including artists Blake Ferris and Robert Schramm continue to make uranotype prints today. https://en.wikipedia.org/wiki/Uranyl_nitrate If that is indeed the case, then I should get a reading that is higher than the immediate background reading.

    Thomas

  3. #33
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    Re: The Uranotype Thread

    A Hundred Yards Over the Rim

    http://spiritsofsilver.com/yahoo_sit...2422_large.jpg

    At one time known as The Air Flight Inn back in the 40's and 50's, and probably 60's, the cafe was featured in a 1961 Twilight Zone episode A Hundred Yards Over the Rim according to the current owner and sole occupant of Grant, California, Chris who lives directly across the street in a former filling station which he also owns and one of the two structures in Grant. According to the 72-year old long-time Owens Valley resident the café was originally owned by John Grant who was a business partner with Howard Hughes back in the 1940's when the plan was to build an experimental airfield for Hughes in the area. The airfield never materialized but the cafe is readily recalled by long time residents of the area.

    Thomas
    Last edited by tgtaylor; 27-May-2017 at 19:12.

  4. #34

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    Re: The Uranotype Thread

    DEAR THOMAS,

    Looks really nice! I did a How To video on Uranotypes for APIS 2013 and will be presenting an update again at APIS in September.
    https://www.youtube.com/watch?v=iwXuZwtjHks

    Here is an example of one of my 5 year old uranotypes.Click image for larger version. 

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  5. #35
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    Re: The Uranotype Thread

    Hi Bob,

    I saw your Video when I first got into this process and posted a link to it earlier in this thread. Rather than using a light box, I print using the sun so I was not able to get exposure guidance from it but otherwise it was a real help in getting started. I am looking forward to the update so maybe you could post a link to it here when it becomes available.

    That's an excellent print of the grapes which makes for a fine subject matter for the Uranotype. Finding suitable subject matter is challenging and of the 4 prints I have linked to above, only two are worthy: The Toaster, for example, looks much better as a Cyanotype - which I ended-up mounting on museum board - but I am always on the lookout for a subject. I have about 30 grams of uranyl nitrate along with ~ 15mL in mixed solution remaining so maybe your update at APIS next month will generate some interest in the process.

    Thomas

  6. #36

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    Re: The Uranotype Thread

    DEAR THOMAS,

    Yes, choosing which subjects to print on urano is a trick. It appears that uranos were popular for portraiture during the second half of the 19th C due to their warm color but, as the short essay in an earlier post says, they were replaced by the more sensitive silver processes. As in my video, I use Potassium Dichromate as a contrasting agent to snap up the highlights while leaving the deeper "old burgundy" shadows. As you have discovered the urano process has a veeeeeeeeeeeeeeery looooooooooooooong scale and needs some negs with SERIOUS density ranges to get anything near a light highlight and deep shadow on the same print!

    I was in a rush and, of course, the bulb on my NuArc 26-1KS blew and I wasn't keeping extras at that time (learned THAT lesson!!!) so exposed 3 uranos for a show in Brussels in the sun. Nice results. Then I got quantitative and bought a Light Measure long wavelength exposure meter so, once I nail the neg/paper combo, I hope to be more efficient in printing.

    I will be presenting comparison prints on about 7 popular papers and the results of increasing the pigment load onto Pictorico Ultra Premium as compared to the Letterpress film I usually use. This new neg looks like it just might do justice to the urano scale index.

    If time permits, I may try some additional toners as well.

    Access to uranyl nitrate is becoming more and move difficult. I found a supplier selling small quantities at reasonable prices two years ago but they have discontinued selling it. I have found another supplier and will place a test order but I am beginning to think that we need to treat uranyl nitrate like a really good printing paper...find one? Buy a LARGE supply! LOL!!!

    CHEERS!
    BOB


    Quote Originally Posted by tgtaylor View Post
    Hi Bob,

    I saw your Video when I first got into this process and posted a link to it earlier in this thread. Rather than using a light box, I print using the sun so I was not able to get exposure guidance from it but otherwise it was a real help in getting started. I am looking forward to the update so maybe you could post a link to it here when it becomes available.

    That's an excellent print of the grapes which makes for a fine subject matter for the Uranotype. Finding suitable subject matter is challenging and of the 4 prints I have linked to above, only two are worthy: The Toaster, for example, looks much better as a Cyanotype - which I ended-up mounting on museum board - but I am always on the lookout for a subject. I have about 30 grams of uranyl nitrate along with ~ 15mL in mixed solution remaining so maybe your update at APIS next month will generate some interest in the process.

    Thomas

  7. #37

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    Re: The Uranotype Thread

    Quote Originally Posted by BOB KISS View Post
    DEAR THOMAS,

    Yes, choosing which subjects to print on urano is a trick. It appears that uranos were popular for portraiture during the second half of the 19th C due to their warm color but, as the short essay in an earlier post says, they were replaced by the more sensitive silver processes. As in my video, I use Potassium Dichromate as a contrasting agent to snap up the highlights while leaving the deeper "old burgundy" shadows. As you have discovered the urano process has a veeeeeeeeeeeeeeery looooooooooooooong scale and needs some negs with SERIOUS density ranges to get anything near a light highlight and deep shadow on the same print!

    I was in a rush and, of course, the bulb on my NuArc 26-1KS blew and I wasn't keeping extras at that time (learned THAT lesson!!!) so exposed 3 uranos for a show in Brussels in the sun. Nice results. Then I got quantitative and bought a Light Measure long wavelength exposure meter so, once I nail the neg/paper combo, I hope to be more efficient in printing.

    I will be presenting comparison prints on about 7 popular papers and the results of increasing the pigment load onto Pictorico Ultra Premium as compared to the Letterpress film I usually use. This new neg looks like it just might do justice to the urano scale index.

    If time permits, I may try some additional toners as well.

    Access to uranyl nitrate is becoming more and move difficult. I found a supplier selling small quantities at reasonable prices two years ago but they have discontinued selling it. I have found another supplier and will place a test order but I am beginning to think that we need to treat uranyl nitrate like a really good printing paper...find one? Buy a LARGE supply! LOL!!!

    CHEERS!
    BOB

  8. #38

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    Re: The Uranotype Thread

    APIS 2017 URANOTYPE UPDATE VIDEO now on YouTube: https://www.youtube.com/watch?v=BbAG1Re5LRo

  9. #39
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    Re: The Uranotype Thread

    Hi Bob,

    Thanks for posting the link to the 2017 update which I found highly informative and the prints exquisite. I also have been brush coating (single coat) Platinum Rag paper, adding 4 drops of dichromate, which I allow to dry for about 1.5 hours before exposure in the sun. Next chance I get, I'm going to try your double coating method with the 12 hour wait between coating and exposure.

    Thomas

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