Ultra violet Leds

Discussion in 'Alternative Processes' started by numnutz, Sep 19, 2005.

  1. numnutz

    numnutz Member

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    I have been looking out fro some white Light emmiting diodes to make myself a ring light for macro work - it is probably cheaper than a ring flash. I noticed that one supplier I looked at had a range of UV leds - I wonder if these could be use in a matrix say 20 x 20 leds (or more) to be used as an UV exposure source when exposing alt process negatives.
    A supplier info page is here: (no recomendations)
    http://www.lsdiodes.com/shop/index.php?main_page=product_info&products_id=15

    I am not sure about brightness it quotes in MCD'S that I havn't heard of before.

    nn :smile:
     
  2. Donald Miller

    Donald Miller Member

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    I experimented with these (395 nm) for exposing Azo and the results were not workable...alt process would be even more unworkable.
     
  3. numnutz

    numnutz Member

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    Thanks for the info - I gather that the MCD abbreviation stands for milli-candle power so would not have the intensity required.

    nn :smile:
     
  4. Donald Miller

    Donald Miller Member

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    There is both the intensity and also possibly the nm emission spectrum to consider...Not all UV is the same UV.
     
  5. Lee L

    Lee L Member

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    http://superbrightleds.com/leds.htm has some 2000 mcd UV LEDs. Probably still not up to the job, but nearly 4 times the output of your indicated supplier.

    Single unit price is also $1.79 compared to $0.60 of the lower output unit.

    Yes, mcd stands for millicandle, 1/1000 th of a standard candle flame output.

    Lee
     
  6. Loose Gravel

    Loose Gravel Member

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    numnutz, mcd is indeed milli-candela. FYI, This is a unit of luminous intesity, which means it is referenced to what the human eye sees and not what sensors or photographic materials see. The human eye doesn't see well at blue or violet. So something that is dim to the eye, can be bright to a piece of film or paper.
     
  7. hortense

    hortense Member

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    mcd

    Milli-candella.