Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,702   Posts: 1,548,466   Online: 844
      
Page 17 of 24 FirstFirst ... 711121314151617181920212223 ... LastLast
Results 161 to 170 of 238
  1. #161
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    23,069
    Images
    65
    It did not seem to look like that at all. We had drawings (side view) of a plate holder with a chamber behind the holder for the Hg. Mercury was not needed for viewing. They were mounted in small velvet cases with doors that opened to expose the plate.

    PE

  2. #162

    Join Date
    Oct 2006
    Shooter
    Medium Format
    Posts
    131
    Quote Originally Posted by holmburgers View Post
    Something else that confuses me, if mercury is a powerful sensitizing agent, as in astro-photography hyper-sensitization, and also a powerful fogging agent, how come it doesn't adversely affect the Lippmann emulsion?

    If you read Neuhauss' journals, http://holoforum.org/data/lippmann/N...s_Journals.pdf (written in German though), you'll see he encountered tons of problems with mercury. Fogging seems to have been a huge issue. He explicitly mentions "Quecksilberschlieren".

  3. #163
    Lionel1972's Avatar
    Join Date
    Oct 2009
    Location
    France
    Shooter
    4x5 Format
    Posts
    199
    WOW! Good luck Chris with your first Lippmann plate. Can't wait to see the results.
    PE, you're so lucky! Can you tell us more about the experience of looking at a Lippmann plate? How different is it from looking at a chrome on a light table?

  4. #164
    Lionel1972's Avatar
    Join Date
    Oct 2009
    Location
    France
    Shooter
    4x5 Format
    Posts
    199
    Just found out that I missed a good opportunity to see actual Lippman plates in Paris in november 2009, but at that time I didn't even know about them. Someone blogged about it and even took a pretty decent picture of a Lippmann plate :

    http://www.viedegeek.fr/article/expo...anophotonique/

    The picture :


  5. #165
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    23,069
    Images
    65
    Lionel;

    You view the plate by incident light at an angle and you view the reflected image as shnown in your photo above. The color is intense and real, being the actual colors recorded instead of a dye image. The images can only be viewed by one or two people at a time due to the limited viewing angle.

    PE

  6. #166
    Lionel1972's Avatar
    Join Date
    Oct 2009
    Location
    France
    Shooter
    4x5 Format
    Posts
    199
    Thank you PE. What about the contrast and apparent lattitude of exposure? In the image I posted, the contrast doesn't come up really well but I guess that is due to the digicam settings used. How would you compare it to a large size autochrome (viewing angle aside of course)? Do you think it would be possible to use a loupe on Lippman plates given the small viewing angle?

  7. #167
    holmburgers's Avatar
    Join Date
    Aug 2009
    Location
    Rochester NY (native KS)
    Shooter
    Multi Format
    Posts
    4,420
    Images
    2
    Hologram, thanks for mentiong the 'quecksilberschlieren', I guess my suspicion was correct.

    Lionel, thanks for the encouragement and the picture. We're getting a pretty good collection of Lippmann images on this thread.

    Quick question; any recommendations (I'm looking at you Hologram ) on substituting Sorbitol for Glycerin?

    [update, two hours later... whoa, I get it! "quecksilber" is quicksilver, and schlieren is streak, as in Schlieren photography which captures fluid movements of air by small variations in density, streaks if you will. I love cognates and borrowed words...]
    Last edited by holmburgers; 01-27-2011 at 12:33 PM. Click to view previous post history.

  8. #168
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    23,069
    Images
    65
    Lionel;

    The color saturation in the plates we viewed was great but the viewing angle gave us a limited latitude in the image tone itself. Can you visualize that? Good color, good saturation, limited tone. It was nothing like the photo above. They were far superior.

    PE

  9. #169

    Join Date
    Oct 2006
    Shooter
    Medium Format
    Posts
    131
    Quote Originally Posted by holmburgers View Post
    Quick question; any recommendations (I'm looking at you Hologram ) on substituting Sorbitol for Glycerin?

    [update, two hours later... whoa, I get it! "quecksilber" is quicksilver, and schlieren is streak, as in Schlieren photography which captures fluid movements of air by small variations in density, streaks if you will. I love cognates and borrowed words...]
    Post-swelling the emulsion with sorbitol is probably a better solution than doing it with glycerin. But both may leave the surface somewhat tacky. Citric acid might be even more convenient.

    Yes, "streak" may be a pretty good translation for Schlieren.

  10. #170
    holmburgers's Avatar
    Join Date
    Aug 2009
    Location
    Rochester NY (native KS)
    Shooter
    Multi Format
    Posts
    4,420
    Images
    2
    Thanks,

    I think my Sorbitol solution is 70% (I'll have to check). How should I compensate for the difference? Is there a standard conversion, something to go off of?
    If you are the big tree, we are the small axe



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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