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  1. #21

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    Ole - Respectfully, I am not looking for disagreements. Development by inspection using a weak light of the film's least sensitive color is something I did, too. The fact that you don't use a green light with Efke 25 rather affirms that it might be more green sensitive than conventional films, no?

    End of thread for me until I can find, or make, an authoritative source showing the log sensitivity of Efke 25 such as Kokak shows for Tri-X 320. It would benefit all of us to settle the matter with true metrics.

  2. #22

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    All you have to do is figure out the filter exposure factor for a 25 red. With normal pan it is 3 stops. With Efke , iti s much more. I did it, but no longer use the film so I do not remember the exact number. 3 extra stops barely puts anything on the neg.

    Orange and red filter require much greater correction.

  3. #23

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    Quote Originally Posted by Ronald Moravec
    All you have to do is figure out the filter exposure factor for a 25 red. With normal pan it is 3 stops. With Efke , iti s much more. I did it, but no longer use the film so I do not remember the exact number. 3 extra stops barely puts anything on the neg.

    Orange and red filter require much greater correction.
    Which begs the question; why use those filters if that part of the spectrum is practically missing already?

  4. #24
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    Quote Originally Posted by jjstafford
    Which begs the question; why use those filters if that part of the spectrum is practically missing already?
    What don't you like a challenge?

  5. #25

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    Quote Originally Posted by garryl
    What don't you like a challenge?
    Sisyphusian 'challenges' are not.

  6. #26
    Ole
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    Quote Originally Posted by jjstafford
    Your experience? You said that Efke 25 is red-blind, and I asked if you have ever developed it under red safelight. You clearly have not or you wouldn't dare say that.

    I wasn't born yesterday.
    I have answered this already. I do not use a weak green safelight with EFKE 25, because i can use a STRONG red one.

    The burden of evidence is on you, since my opinion (for a change) tallies with not only the manufacrurer's specifications, but also with all photographic literature from Willi Beutler's 1947 "Dunkelkammerpraxis" to the present day. You are the one claiming increased red sensitivity, you prove it.
    -- Ole Tjugen, Luddite Elitist
    Norway

  7. #27

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    Quote Originally Posted by Ole
    I have answered this already. I do not use a weak green safelight with EFKE 25, because i can use a STRONG red one.
    This is quite a wonderful bit of news!

    All APUG users should be indebted to you for that informaion. Now all of them can load and develop Efke 25 in bright red light. Perhaps Efke will pick up on this as an advertised advantage. I'll pass on this information to Efke so that they can confirm this and recognize you as the authoritative source.

  8. #28

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    Quote Originally Posted by Ole
    I have answered this already. I do not use a weak green safelight with EFKE 25, because i can use a STRONG red one.
    This has been a profitable thread so far.

    John at J&C says: "They are not Orthochromatic though and do see the red part of the spectrum to some degree. Above approximately 650nm they are approaching zero sensitivity. The question is not one of the brightness of the red light but it's wavelength. Even a dim red light at 600nm will fog the film. A bright red ight at 675nm will have little effect. [...]"

    Now add to this the fact that the young, healthy human eye cannot see above about 640nm, and the aged eye even less (you are over fifty, no?), then we have an interesting situation. It appears that you (Ole) have two special advantages; first, your eyesight is not typical because you can see farther into red than most mortals, and second, you have a red light source you should share with the rest of us.

    Please post the source for this red light and be our hero!

    Sincerely,
    John
    Last edited by jjstafford; 06-19-2005 at 06:37 PM. Click to view previous post history.

  9. #29

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    Quote Originally Posted by jjstafford
    ..to some degree. Above approximately 650nm they are approaching zero sensitivity.
    So what, where is this extended red sensitivity you started all this fuss about? It is sensitive to red, to some degree, yes. But not as much as Tri-X, and certainly not more so than Tri-X, which is what you stated earlier.

    I do certainly not understand your attityde, and why you try to change the subject from the red sensitivity to some darkroom light when you notice that you were wrong.
    You have no right to be rude to Ole, who has been clear and nice in his posts, contrary to yourself.
    Why would he lie about him developing with a red light? If it works, it works.

  10. #30

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    [QUOTE=jjstafford]Ole - Respectfully, I am not looking for disagreements.




    Oh, really?

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