Chromalin proofing. Is it UV ?

Discussion in 'Alternative Processes' started by George Papantoniou, Oct 24, 2006.

  1. George Papantoniou

    George Papantoniou Member

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    I can get my hands on a Chromalin proofing machine, the kind that exposes contacts with a kind of blueish light. If you have seen this process done before, you'll know what I am talking about. The lamp is in a rectangular device and on top there is a glass where the film/chromalin sandwich is placed. The cover is closed and an exposure is made (the whole thing works like a sophisticated contact printer).

    I am not sure whether the lamp is producing UV frequencies. If it is, I could use it for alt photo processes, such as gum and platinum.

    Does anyone know if it would work ?
     
  2. David Lingham

    David Lingham Member

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    George
    A Cromalin proof was a form of proofing I used for many years in the graphic arts industry. Pre digital when film still was used for colour separation, each of the final CMYK litho positives was in turn put in contact with a base material that had been laminated, once for each colour. The film and laminated base were put in a vacum frame and exposed to uv light for a pre determined time. Then processed, relaminated and the procedure repeated for the next colour. A very long and not very accurate way of proofing. The light sources are UV and are usually very powerful. They should normally be filtered back with a dialux filter.
     
  3. George Papantoniou

    George Papantoniou Member

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    Thank you Dave,

    As you describe things the proofer that I am being offered must work for alt photo printing processes... a strong UV light is exactly what is needed...

    I am feeling lucky today. I hope the d*** thing is still in working condition...
     
  4. David Lingham

    David Lingham Member

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    George

    UV exposure frames for cromalin were either an enclosed box with the light mounted on the floor pointing up and a flip top vacum frame on top, or the earlier ones would have the light suspended above pointing down at the vacum frame, these must have a safety curtain around the light source for your protection! Make sure you have that included. Good luck.
     
  5. Claire Senft

    Claire Senft Member

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    I will ask my daughter. She is a journeyman in the graphic arts industry. When she first started on her apprenticeship she was doing Cromalin proofing..this was in pre-digital days. I am almost certain that the answer will be yes because the proofing was done from films.
     
  6. George Papantoniou

    George Papantoniou Member

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    Dave, it's not that old. It's the kind with the lamp under the glass and so I will be 100% protected from the lamp's UV (although I could use a tan, people would think I went skiing...:smile:. The problem is that someone has taken the lamp's fan out and now I have to find a way to replace it before I put it to work. Anyway, finding a fan that will work for it won't be too difficult.
     
  7. George Papantoniou

    George Papantoniou Member

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    As for the digital/analog proofing debate, those people (that offer me the proofer) still work analog. They just bought a new (analog) one, so they're getting rid of the old.