Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,206   Posts: 1,531,805   Online: 842
      
Results 1 to 9 of 9
  1. #1
    ParkerSmithPhoto's Avatar
    Join Date
    Jan 2010
    Location
    Atlanta, GA
    Shooter
    Medium Format
    Posts
    797
    Images
    6

    LED Bulb in Condenser head

    Has anyone experimented with a LED Bulb in Condenser head to avoid heat and popping. Or maybe a compact fluorescent? Any issues with the spectrum for VC papers?
    Parker Smith Photography, Inc.
    Atlanta, GA

    Commercial & Fine Art Photography
    Portrait Photography

  2. #2
    dehk's Avatar
    Join Date
    Aug 2010
    Location
    W Michigan
    Shooter
    Multi Format
    Posts
    882
    I know one problem with a compact fluorescent, it has to warm up. I'm interested to hear about using a LED bulb as well.
    - Derek
    [ Insert meaningless camera listing here ]

  3. #3
    Mainecoonmaniac's Avatar
    Join Date
    Dec 2009
    Shooter
    Multi Format
    Posts
    2,943
    Images
    6
    I think LEDs are the way to go. No warm up. Take a look at this:

    http://www.deadbread.com/crumbs/23c.html

  4. #4
    MattKing's Avatar
    Join Date
    Apr 2005
    Location
    Delta, British Columbia, Canada
    Shooter
    Multi Format
    Posts
    12,235
    Images
    60
    Someone here on APUG actually sells an LED Lamp House for Omega D Series enlargers: http://www.apug.org/forums/forum379/...-enlarger.html
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  5. #5
    Roger Cole's Avatar
    Join Date
    Jan 2011
    Location
    Suburbs of Atlanta, GA USA
    Shooter
    Multi Format
    Posts
    3,828
    Quote Originally Posted by MattKing View Post
    Someone here on APUG actually sells an LED Lamp House for Omega D Series enlargers: http://www.apug.org/forums/forum379/...-enlarger.html
    Yep. As I said in that thread, I bought one of these. That was right after my last printing session and busy weekends have kept me from trying it. I have a three day weekend coming up this week though and lots of negatives to print, so I'll be trying it out. I'll report back here.

    It is a very well made piece of gear.

    Parker, if you're really interested in getting one I might be persuaded to sell that D2 back to you (minus the grain focuser which is a huge improvement over my old one!)

  6. #6
    Laurent's Avatar
    Join Date
    Oct 2004
    Location
    France
    Shooter
    Multi Format
    Posts
    1,209
    Blog Entries
    22
    Images
    137
    Quote Originally Posted by Mainecoonmaniac View Post
    I think LEDs are the way to go. No warm up. Take a look at this:

    http://www.deadbread.com/crumbs/23c.html
    Thanks (millionS of them) for the link. I'm using a similar setup but did not drive so many tests (I'm only using white LEDs).

    My enlarger is a Priox, the setup works fine (my difuser is baking paper, I have to test some material they use in theaters. The white plexi cost me too much (3 stops)).
    My only issue is converage on the edges for 4x5 but I'm afraid this has to do with my enlarger (it's a 9x12 one)
    Attached Thumbnails Attached Thumbnails IMG_2670.JPG   IMG_2663.JPG   IMG_2666.JPG  
    Laurent

    ---------------------------------------------------------------
    Only dull people are brilliant at breakfast (Oscar Wilde)

    My APUG Blog

  7. #7

    Join Date
    Apr 2010
    Location
    Hickory, NC
    Shooter
    4x5 Format
    Posts
    32
    Quote Originally Posted by Laurent View Post
    The white plexi cost me too much (3 stops)).
    Try 1/8" #2447 white acrylic. It cuts only 50% (1 stop). If you can see the LED's themselves through the acrylic, try wet sanding the surface closest to the LED's to create a ground glass effect. Alternatively, try the 3/16" sheet which cuts 58% of the light. eStreet Plastics (www.estreetplastics.com) is a good source of acrylic in small quantities.

    Also, make sure to consider proper thermal management when using LED's. Overheating dramatically shortens their life and significantly lowers their light output.

  8. #8

    Join Date
    Apr 2010
    Location
    Hickory, NC
    Shooter
    4x5 Format
    Posts
    32
    Quote Originally Posted by ParkerSmithPhoto View Post
    Has anyone experimented with a LED Bulb in Condenser head to avoid heat and popping. Or maybe a compact fluorescent? Any issues with the spectrum for VC papers?
    The problems with commercial LED replacement bulbs in a condenser lamp house are multiple. Firstly, the condensers are designed with a round, even light source in mind. Any deviation from evenness or size will manifest as unevenness in light at the easel. Secondly, to keep the bulb in focus the distance to the condensers must be maintained as it was with the original incandescent bulb; most commercial LED's are shorter or longer than the bulbs they replace. Thirdly, LED replacement bulbs have low light output, far less than a typical 150 watt incandescent enlarging bulb, and the light may come out of the bulb directed squarely at the lamp housing, where it is wasted, rather than toward the condenser where it can be directed at the negative. And finally, commercial LED replacements are poor at thermal management, especially in the confines of a condenser lamp house. This manifests as unsteady light output during an exposure and a dramatic shortening of the bulb life span.

    It was to overcome these problems that I designed my own LED lamp house. Unfortunately, as you know, it is available only for the Omega D series enlargers at this time.

  9. #9
    Laurent's Avatar
    Join Date
    Oct 2004
    Location
    France
    Shooter
    Multi Format
    Posts
    1,209
    Blog Entries
    22
    Images
    137
    I'm looking for one of these diffusers (I contacted Kinght Optical, who seem to make what I need http://www.knightoptical.com) but in the meantime I decided to bite the bullet and I doubled the LEDs in my head.

    I arranged them in a larger rectangle, with more density on the edges, hoping this will help in illuminating the corners and edges.
    Laurent

    ---------------------------------------------------------------
    Only dull people are brilliant at breakfast (Oscar Wilde)

    My APUG Blog



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



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