Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 71,501   Posts: 1,571,712   Online: 954
      
Results 1 to 10 of 10
  1. #1
    laz
    laz is offline
    laz's Avatar
    Join Date
    Aug 2005
    Location
    Lower Hudson Valley (NY)
    Shooter
    Multi Format
    Posts
    1,118

    280mm series V.B. Cooke Process Anastigmat Lens

    I could just ask Jim Gallie but......

    Before I became really serious about LF I was knocking around on ebay and on a whim bid a huge definantly non-field 8x10 that, if good for nothing else it, came with a couple of dozen 5x7 and 8x10 film holders I figured were worth more than the camera. (of course once I had the holders I [i]had to have a 8x10 field didn't I ?)

    Anyway it came with a 280mm series V.B. Cooke Process Anastigmat Lens. I was looking at it this morning and saw that it has an ajustable slit on the barrel between the elements. As a LF newbie I'm baffled. What is it for?

    Thanks,
    Bob

  2. #2

    Join Date
    Mar 2005
    Shooter
    Multi Format
    Posts
    3,505
    Many process lenses have such a slit. It is adjustable so that it can be closed (to exclude light) when not in use. The slit accepts a variety of Waterhouse stops.

  3. #3
    Denis P.'s Avatar
    Join Date
    May 2004
    Location
    Croatia
    Shooter
    Multi Format
    Posts
    466
    Images
    9
    Heh, I wanted to write something completely different, guessing about Waterhouse stops or miissing diaphragm lever, but here's what it is - straight from the horse's mouth:

    "Cooke process lenses made after the early 1920s were provided with a removable lens-hood that could be covered with a leather cap. The screw thread that attaches the hood could alternatively receive any process prism fitted with the standard screw. Process Prisms are extremely rare now and are the stuff of museums instead of Ebay. An iris diaphragm was provided at that time instead of the stops with circular openings. A narrow slot in the lens barrel near the front of the lens could receive process diaphragms or gel filters (of graphic arts quality) if desired. The slot can be opened and closed by revolving the inscription tube."

    - cited from:

    http://www.cookeoptics.co.uk/cooke.n...viewcamera2002

    HTH,

    Denis

  4. #4
    laz
    laz is offline
    laz's Avatar
    Join Date
    Aug 2005
    Location
    Lower Hudson Valley (NY)
    Shooter
    Multi Format
    Posts
    1,118
    Quote Originally Posted by Denis P.
    or gel filters (of graphic arts quality) if desired. The slot can be opened and closed by revolving the inscription tube."
    Thanks Denis! That fits prefectly with what I believed the camera to be, a commercial copy camera.

    I'd been to the Cooke website before but never saw the tidbit you quoted

    Soon I'll plunk that puppy onto the Korona and see what image it produces for me.

    -Bob

  5. #5
    jimgalli's Avatar
    Join Date
    Sep 2002
    Location
    Tonopah Nevada
    Shooter
    ULarge Format
    Posts
    3,417
    Blog Entries
    2
    Images
    156
    An educated guess is it won't cover 810 but should be very nice on 5X7. Does the Korona have a Packard?
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

    http://tonopahpictures.0catch.com

  6. #6
    laz
    laz is offline
    laz's Avatar
    Join Date
    Aug 2005
    Location
    Lower Hudson Valley (NY)
    Shooter
    Multi Format
    Posts
    1,118
    Quote Originally Posted by jimgalli
    Does the Korona have a Packard?
    The copy camera that the lens came from did. I should mount it on the board I put the lens in, correct?

    Quote Originally Posted by jimgalli
    An educated guess is it won't cover 810 but should be very nice on 5X7.
    The camera came with both an 8x10 and 5x7 back so I guess this is the lens for the 5x7......

    Thanks Jim!

    -Bob

  7. #7
    jimgalli's Avatar
    Join Date
    Sep 2002
    Location
    Tonopah Nevada
    Shooter
    ULarge Format
    Posts
    3,417
    Blog Entries
    2
    Images
    156
    Bob, Copy cameras worked at different distances than we normally do with our subjects. When a 280mm is making a 1:1 reproduction the bellows is actually at 550+mm so your 280 @ infinity just became a 560mm. It would likely cover 11X14 at that distance. The angle of light just keeps making a bigger circle as the bellows increases. So it would probably be a great 8X10 lens for copying.

    In my Kodak 2D I mounted the biggest packard I could squeeze between the bellows folds right up against the front of the camera. That way the packard travels with the camera and you can use the same packard with any number of barrel lenses that may come along. If you're using a shuttered lens, you simply open the packard up and the rear element of a modern shuttered lens rests inside the packard's open aperture.
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

    http://tonopahpictures.0catch.com

  8. #8
    laz
    laz is offline
    laz's Avatar
    Join Date
    Aug 2005
    Location
    Lower Hudson Valley (NY)
    Shooter
    Multi Format
    Posts
    1,118
    Quote Originally Posted by jimgalli
    Bob, Copy cameras worked at different distances than we normally do with our subjects. When a 280mm is making a 1:1 reproduction the bellows is actually at 550+mm so your 280 @ infinity just became a 560mm. It would likely cover 11X14 at that distance. The angle of light just keeps making a bigger circle as the bellows increases. So it would probably be a great 8X10 lens for copying.
    Ahhh I get it!

    In my Kodak 2D I mounted the biggest packard I could squeeze between the bellows folds right up against the front of the camera. That way the packard travels with the camera and you can use the same packard with any number of barrel lenses that may come along. If you're using a shuttered lens, you simply open the packard up and the rear element of a modern shuttered lens rests inside the packard's open aperture.
    Wow, thanks for that info, that saves a lot of trouble and opens up new possibilities for aquiring more lenses in barrel!

    -Bob

  9. #9
    jimgalli's Avatar
    Join Date
    Sep 2002
    Location
    Tonopah Nevada
    Shooter
    ULarge Format
    Posts
    3,417
    Blog Entries
    2
    Images
    156
    Quote Originally Posted by laz127
    ....and opens up new possibilities for aquiring more lenses in barrel!-Bob

    Crap. More competition.
    He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

    http://tonopahpictures.0catch.com

  10. #10
    laz
    laz is offline
    laz's Avatar
    Join Date
    Aug 2005
    Location
    Lower Hudson Valley (NY)
    Shooter
    Multi Format
    Posts
    1,118
    Quote Originally Posted by jimgalli
    Crap. More competition.
    Think positivly Jim. Better customer.



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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