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  1. #1
    holmburgers's Avatar
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    Kodak Color Densitometer Model 1 (Art Deco) - A question about the color filters.

    Hi all,

    I have an opportunity to buy an old Kodak Color Densitometer Model 1. However, judging from the picture (the 1st attached photo) the filter "tab" is missing, as evidenced by the 2nd photo of what I believe to be a complete unit.

    So, without the filter tab, is this unit still useful for simple black & white densitometry (non pyro negs)?

    Moreover, it doesn't seem like it would be too hard to make my own filter tab, if indeed it is only a strip of metal with 3 patches of filter material. I guess the question then is what are the appropriate filters to use. I have Wratten 29, 47B and 58's that I could cut off a small patch from and mount it in some cardboard.

    Your expertise is most appreciated!

    Thanks,

    Chris
    Attached Thumbnails Attached Thumbnails Kodak Color Densitometer Model 1.JPG   Kodak Color Densitometer Model 1 with filters.JPG  

  2. #2
    Mike Wilde's Avatar
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    I'm not up on what it uses for the intensity sensing. If it is an extinction type, give it a pass unless you want it for a historical boat anchor/shelf queen.

    I would hold out for an old MacBeth. They are solid as a rock. The only achillies heel is their photmultiplier tube.

    I am pretty sure that they used filters similar to what you are quoting. teh filter in mine are a bit mottled, but still give me reasonable numbers, so I am not going to screw with them.
    my real name, imagine that.

  3. #3
    holmburgers's Avatar
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    Hi Mike, thanks much for your input.

    It works on the visual princicple; that is, you have to match a reference patch by turning the wheel and the readout is your density. Does that make it boat anchor worthy?

    I've heard that these are surprisingly accurate, foolproof and adequate for basic densitometry and that's what I'm looking for.

  4. #4
    Mike Wilde's Avatar
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    Well, if it is colour, then how do you visually judge the density of just one part of the spectra?
    I am always baffled about colour measurement electronically; to throw my visual system into the measurement would confuse me even more.
    my real name, imagine that.

  5. #5
    holmburgers's Avatar
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    I honestly don't know. It sounds terrible on paper, but in practice I think it's a perfectly satisfactory method. Our eye's are quite a sensitive instrument and apparently matching densities isn't that tricky. Though I agree, it seems like introducing color would complicate things... though if both patches are colored it shouldn't be too hard.

  6. #6
    Photo Engineer's Avatar
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    I have one and it works reasonably well for an antique of this nature.

    I really don't see anything missing in the photo. The horizontal silver strip is the "filter tab" with an R/G/B filter set that can be moved into position. The yellow wheel on the right back is the density adjust wheel. Presuming they work as designed there should be no problem.

    Internally there are 2 light bulbs and an adjustment pot. That is about it. The case is pretty empty otherwise.

    PE

  7. #7
    holmburgers's Avatar
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    Thanks Ron, that sounds great.

    I like old stuff... they don't make things like they used to.

    What about Mike's concern, "Well, if it is colour, then how do you visually judge the density of just one part of the spectra?"

  8. #8
    L Gebhardt's Avatar
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    I had one, and it worked well enough. But it's slow, and not as accurate or repeatable (the fault of my eyes, no doubt) as the electronic ones. It looks like the one you show has the filter, but maybe not the wooden case. I never used mine for color, but I did try it and it seemed to work ok when I compared it to my new xrite 810.

  9. #9
    holmburgers's Avatar
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    I mainly want it to compare b&w separation negatives. For instance, I made an in-camera separation of a scene using color filters the other night. So, I can check the gray-scale included in the image to see whether or not I have equally exposed seps.

    I'm excited to give it a go. I guess I'll just have to recalibrate it once my eyes start giving out...

  10. #10
    Photo Engineer's Avatar
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    Since this device relies on the human eye, it will probably vary in result from person to person, but basically you are matching two dots, one within the other. You match densities. There is not much provision for calibration.

    OTOH, they use pretty much the same filters as other, larger and more expensive densitometers use. From that POV they are quite usable.

    You do not need a color densitometer to compare separation negatives as they are B&W. However, this unit has a B&W mode.

    PE

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