Distance of UV unit from printing frame

Discussion in 'Alternative Processes' started by colrehogan, Feb 14, 2005.

  1. colrehogan

    colrehogan Member

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    How far are your light units away from your printing frame? How do you support them? Hope that makes sense. I currently just use the unit sitting on the table, so there's not much distance between the frame and the bulbs.

    I was going through the thread about the Dmax on COT 320 and saw that people were using 10 and more minutes for their prints and was just wondering. I do my printing in the living room and with three cats in the house, I have to block the light so the cats don't stare at it.
     
  2. Joe Lipka

    Joe Lipka Member

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    I have an old UV box I purchased from the Palladio Company. It sits directly on top of my vacuum frame. The bulbs are about 10 cm (2") from the negative.
    Our cats hate me, so they don't bother me at all. That, and the fan on the UV light box drives them away.
     
  3. photomc

    photomc Member

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    Diane, from a previous thread here - sorry at work and can not search for it, seems like the average was 2-3 inches from light to negative. If you can, search for the post, if not I will look tonight when I get home. Are you leaving the side door open? Not sure where the light is coming from you need to block..on mine it's easy to see since it is not enclosed.

    Just noticed Michael Mutmansky is signed on...if anyone can give a correct answer it will be him..
     
  4. Michael Mutmansky

    Michael Mutmansky Member

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    Diane,

    It depends on the spacing of the lamps a bit.

    I would try to keep the glass of the frame about 3 inches off the bottom of the lamps unless you have the lamps spaced more than about 1/2" apart.

    If you get closer, you start to risk getting stripes from the gaps between the lamps, and further away won't really help and will increase the printing time a bit.

    Ultimately, you have to test your conditions and see what works. If you have a well designed unit with minimal spacing and a good reflector behind the lamps, you could probably do 2" without any problems at all.


    ---Michael
     
  5. colrehogan

    colrehogan Member

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    I have an Edwards Engineering 11x14 unit. The B&S 11x14 frame is a little too wide and the door doesn't close snugly.

    I block the light that is getting out with cardboard from the box and stand between the light and the cats when I'm opening the door. They like to lay on the couch behind me when I'm printing. I have the unit on a card table in the middle of the living room.
     
  6. photomc

    photomc Member

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    Now I understand ....and yes there would be reason for concern with them looking at the light for too long - IMO. Perhaps a small drape of some type, I use my darkcoth on the prototype.

    Thanks for the comments Michael....as always welcome input.
     
  7. WarEaglemtn

    WarEaglemtn Member

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    Just get UV protection sunglasses for the cats.