Fibre optic light cables for Durst Pictochrom

Discussion in 'Darkroom Equipment' started by schlger, Jan 23, 2011.

  1. schlger

    schlger Member

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    In the head of the Pictochrom, the light is passed from the mixing box through 3 fibre optic glass light cables through RGB filters to the light receptor cells. I have to replace two of them, because too much glass fibres are broken. Does anyone know where I cab get them?
    Here are the dimensions:
    Length: 20 cm
    outer diametre: 4mm
    diametre of the glass fibres: 1mm
    diametre of both end caps: 4mm

    There is enough space in the head to use longer cables up to 50cm.

    Thank you very much for your tips.
    Gerhard

    Than
     
  2. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    Gerhard ,

    I dont think you can change them. Because you need to know the working specifications of the fiber and you need to be able to attach to the connector. Its specialists business because you need equipment to trim the each end , you need special equipment to check the fiber and the connector aligned.
    Before going to lots of expense and disasters , contact with the manufacturer and get help.
    Fiber optic cables have variable prices and their technology change every year. You can find 1 meter cable from 2 dollar to 4000 dollar.
    I think if they change the cables , they change 3 of it due to calibration.
    This is what I learned from 1500 pages catalogs , their catalogs weight more than 3 kilograms.
    Contact with the manufacturer or the service.

    Best ,

    Umut
     
  3. ic-racer

    ic-racer Member

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  4. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    ic-racer ;

    I am no expert but these fiber optics are acrylic. You can use it to spot light of garments at a store but I dont think they are suitable for RGB business. Fibers are like optics and optical grade glass makes better results .

    What do you think ?

    Umut
     
  5. ic-racer

    ic-racer Member

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    These cables just carry color info to the sensors. More likely than not, if there is any alteration in the color sensing, it would be more likely from faded filters. I'd think any fiber optic cable that looked clear (and not yellow) should work fine.

    BTW, I know the green filters on the sensor on the Omega closed loop system can fade and alter the response of the system.

    http://www.apug.org/forums/viewpost.php?p=777889
     
  6. ic-racer

    ic-racer Member

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    Mustafa, you may be interested in the engineering consequences of the Omega vs Drust system. In the Omega system, the sensors are mounted right on the mixing box (different set of sensors in each mixing box) and connect to the main system with a very low voltage cable.

    OMEGA: Advantage, no fiber optics to go bad, but disadvantage is that each mixing box has to be calibrated. Also, specific to the Omega, the low voltage connector to the light box will really mess up the calibration if there is just the slightest bit of oxidation on the contacts (DeOxit to the rescue).

    DURST: Advantage, only a single set of sensors but fiber optic cable can go bad.
     
  7. Mustafa Umut Sarac

    Mustafa Umut Sarac Member

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    I guess finding a non yellow fiber optic cable is a broad term. Lets put dispersion term in to the place of non yellow term. If everything was that easy , there wouldnt be hundreds of different cables at the market. We are not expert - you and me - and I think best advise would be come from the Durst Service.
    And do you have knowledge to change the cable in the connectors ? In my knowledge , it needs special fiber optic cable cutters and aligners. May be system is so old and everything is so easy.

    mailto:service@durstus.com

    Here is the wisest solution

    Umut
     
  8. ic-racer

    ic-racer Member

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    Actually the acrylic (plastic) fiber optic cables can be easy to work with and likely easily adapted. Any discrepancy in color imparted by the cable will only alter the display value. The closed loop system will not really be affected for color or multigrade printing. However, those cables by Edmund have good transmission as seen below.

    There will be little or no support from Durst for the Pictochrom but you can try. ( http://www.jobo.com/jobo_service_analog/us_analog/bulletins/b030.htm ).

    [​IMG]
     
    Last edited by a moderator: Jan 24, 2011