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Even lighting at an oblique angle

  1. Jul 10, 2006 #1


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    DavesBrain Project 241a - lighting framed pictures

    I want to light a half dozen pictures in 5x7 frames in a display in the corner of my living room (this display will likely be free-standing, like a privacy screen), but I don't want http://www.ikea.com.sg/products/product_display.asp?id=2237" [Broken]. The room is somewhat dimly lit i.e. not enough to do justice to the pics.

    I'm looking for lighting solutions. Maybe you guys'll think of something I didn't.

    My two attempts so far (see attached file):
    1] http://www.ikea.com.sg/products/product_display.asp?id=820" [Broken] mounted near the ceiling, only one per column of pictures. Problem: lights dim with distance and obliquity.

    2] Shadow box frames with 3' of rope light sandwiched between two mattes. Lights are now right next to picture but hidden behind a second matte. I love this solution! Problem: same, really - the string of lights are just not bright enough and are still too oblique. I'm also worried about the unevenness of the light from the rope. My next experiment will be to line the entire picture with white LEDs and see if it's enough light.

    I'm open to suggestions.

    I do have some restrictions:
    - heat generation inside boxes (LED good, incandescent bad)
    - occupied space - I could always move the lights in pic 1 farther back on the ceiling and increase their strength, but I don't want to dominate the whole corner of the room with equipment -or- with light. The more hidden the better.

    Anyone have any improvements or other ideas?

    Attached Files:

    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Jul 10, 2006 #2


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    Have you considered mounting high-intensity white LED's countersunk into the inner bottom edges of the frames? With diffuser lenses, they might provide a nice even illumination.

    edit: Okay, how did you sneak the double-matte and LED stuff into your post after I wrote this, and still show your edit as before me? :grumpy: :tongue:
    Last edited: Jul 11, 2006
  4. Jul 11, 2006 #3


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    They make recessed lighting for just this purpose. The ones I have seen were small globes that could be rotated and did have a relatively small spread to the beam.

    I have seen them like this that have the entire housing and a pivoting lamp:
    http://www.lighting-fixtures-ceiling-fans.com/store/images/HALO_H1499IC.jpg [Broken]

    And I have seen these that are along the same lines, but without the large housing:
    http://www.pegasusassociates.com/products/RecessedLighting/images/4itrimslowvolt/PNL-419-C.jpg [Broken]
    http://www.pegasusassociates.com/products/RecessedLighting/images/4itrimslowvolt/PNL-470-W%20-%20Adjustable.jpg [Broken]
    Last edited by a moderator: May 2, 2017
  5. Jul 11, 2006 #4


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    What is this diffuser lens thing? I'm thinking of trying some sort of prismatic lens to direct thet light onto the picture, but that'd be almost impossible to construct (and I'll need 32 sections!)
  6. Jul 11, 2006 #5


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    Hey, Dave. I just used 'diffuser lens' as a generic term to describe the effect. It can be a really thin layer of frosted glass/plastic, or even just a light coat of nail polish or varnish on the LED. The idea is just to 'fan' the light rather than having it more focused. The trick is to do it without a lot of transmission loss. Another trick is to angle the lights so they overlap in a criss-cross pattern to eliminate shadows.
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