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  1. #11

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    Little or no light for colour.

    Jeff

  2. #12

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    I use the DUKA 10.It's a sodium light and gives very good and safe light and doesn't fog either Fuji or Kodak paper as far as I could tell. That and the DUKA 50( the slightly later version) appear on e-bay from time to time and last time I looked Secondhand Darkoom Supplies had one for a reasonable price.

    pentaxuser

  3. #13

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    Sorry perhaps I didn't expain my future working conditions............Paper out of box, onto easel, exposure, into drum.

    Cheers Dave

  4. #14

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    Than what do you need a safelight for ?????

    Peter

  5. #15

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    I suppose just orintation...(do you make a cup of tea with your eyes shut?) here we go......Another 20 posts of the vertues.

    But all suggestions appreciated.
    Cheers Dave

  6. #16

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    So why are 'colour safelights' made?

  7. #17

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    Quote Originally Posted by Dave Dawson View Post
    So why are 'colour safelights' made?
    Some print RA4 in trays. A safelight would be convenient, wouldn't it?

  8. #18
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    Kodak specifically designed the sensitivity of their color paper for use with a safelight. Actually, there were two. The earlier safelight was used with a slower version of color paper, and the current WR13 is used for the current paper. So, the safelight was designed to work with the paper and vice versa. The safelight is intended for just that, safety. In the dark, one can become disoriented and the safelight helps one maintain orientation towards equipment.

    There is also a dark green safelight that can be used with many panchromatic films. It is called "Min Pan" and exists in the Kodak safelight dataguide.

    The Min Pan safelight is much less "safe" with film due to the high speed and various sensitivities encountered in the field and so its use has declined since introduction, but is still used by Kodak for many purposes. However, it should be rememmbered that current color paper has an ISO rating near 100 for the blue sensitive layer and near 25 for the red sensitive layer.

    PE

  9. #19

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    Quote Originally Posted by Photo Engineer View Post
    There is also a dark green safelight that can be used with many panchromatic films. It is called "Min Pan" and exists in the Kodak safelight dataguide.
    How come dark green? Is the human eye most sensitive at that wavelength, assuming that it is mainly used for development by inspection?

    Thanks in advance.

  10. #20
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    At one time, there was a small dip in the spectral sensitivity of Kodak films that fit this region of the spectrum well for use of a safelight just as there is now a window in the sensitivity of color paper. Not all mfgrs had or have the window in film, but Kodak has it in paper and keeps the safelight in mind. For film it is a long gone issue.

    I suppose that the eye, having max sensitivity in that region does not hurt.

    PE

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