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  1. #1

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    Colorhead settings change as height changes

    Has anyone notice if you change the height of the colorhead then you have to change the YMC settings to compensate for a change in the color temperature of the light source? The changes are not large, but they are needed.

  2. #2

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    Your color temp is changing with head elevation?

  3. #3
    Lopaka's Avatar
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    Perhaps the change is due to longer exposure time?

    Bob
    "I always take a camera, That way I never have to say 'Gee, look at that - I wish I had a camera'" -Joe Clark, H.B.S.S.

  4. #4

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    I have a gossen color-pro 3F color meter, and it also shows that the color temperature of the light source changes as the height of the head changes. Is there any physics that can explain this?

  5. #5
    jd callow's Avatar
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    Quote Originally Posted by Lopaka View Post
    Perhaps the change is due to longer exposure time?

    Bob
    This is the only reason why I can imagine for changing the filter pack on hieght adjustments.

    *

  6. #6

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    Perhaps it is because you are using a meter intended for field use, rather than spot readings of specific areas of a negative?

    Don't most color analyzers for darkroom use have a direct reading, narrow sensor and the Pro F have a rather large integrating chamber?

    Could be you are naturally getting a different area of the neg as you raise the enlarger head; an area of less, more or different total colors?
    Last edited by Kino; 06-05-2008 at 09:25 PM. Click to view previous post history.

  7. #7
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    Filter pack should not change for any reason. Todays papers are adjusted to compensate and eliminate this problem. Something else is going on there.

    PE

  8. #8
    jd callow's Avatar
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    Filter packs will change on longer exposures.

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  9. #9

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    I used a "clear" 5x7 color negative that had an orange cast. I adjusted the color head for daylight balancing the the orange cast to 5500 degrees. My motivation was for making masks from color negative film using daylight balanced TMX 100.

    As I adjusted the height of the colorhead I had to make adjustmments to the head to get a daylight balalnce of 5500 degress.

  10. #10

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    Interesting. No answer unless it is an equal, across the board YCM increase for density loss.

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