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  1. #51
    holmburgers's Avatar
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    Anyone know more about the Mitsumura-Bermpohl Process?

    In 1939, Mitsumura imported a Bermpohl Naturfarbenkamera (tricolor camera) from Germany and Kitazumi was given the task of exploring its use as a part of the color printing process. In the years leading up to Japan's attack on Pearl Harbor, Mitsumura imported two additional tricolor cameras, National Photocolor Lerochrome and Devin Tricolor, from the US. These cameras were used by Mitsumura to develop a photographic printing process which they named the Mitsumura-Bermpohl Process (MBP).

    From Genzou Kitazumi's wikipedia article.

  2. #52
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    From Kitazumi's grandson (interesting discussion about him on the yahoo! group), "I believe MBP process is a part of offset printing process in which color separated negatives are directly transferred to glass plates as screened positives thereby reducing the intermediary steps required in older processes. Less intermediate steps resulted in better transfer of halftone values."

  3. #53
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    This is the best one man thread I've read in a while. Quite a compilation. It's very tempting to delve into this with modern materials. If color film becomes extinct, this will be the Rosetta Stone.

  5. #55
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    Hey Bob, thanks very much!

    I completely agree with you about the demise of color film... and that's probably one of the biggest reasons for starting to think about how to make one of these awesome cameras.

    I guess we should've studied that one at GEH a little closer when we had access to it...
    If you are the big tree, we are the small axe

  6. #56
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    Curtis Color-Scout & Devin 6.5x9cm Tri-Color Camera

    Two gems on eBay currently, and I took the liberty of copying the photographs and preserving them here.

    Here is a manual for the Devin -> http://www.cameramanuals.org/booklet...n_tricolor.pdf
    Attached Thumbnails Attached Thumbnails Curtis 01.JPG   Curtis 02.JPG   Curtis 03.JPG   Devin 01.JPG   Devin 02.JPG  

    Devin 03.JPG   Devin 04.JPG   Devin 05.JPG   Devin 06.JPG  
    If you are the big tree, we are the small axe

  7. #57
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    Devin Diagram

    The light path...
    Attached Thumbnails Attached Thumbnails Devin Diagram.JPG  

  8. #58
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    The above Devin camera just sold on eBay for $1500, even though it's mainly just the skeleton.

    I bet with $1500 you could construct a working prototype of a 3-color camera, optimistically.

    In the pictures above you can see that there are provisions for fine tuning the placement & parallelism of the reflectors. Trying to build the mirrors right into the body without some kind of adjustable frame would be futile, don't you reckon?

    When was the last 1-shot camera made? Consider the advances in machining since then! I bet a CNC machine could eat a 3-color camera for breakfast. National Photocolor still exists and can do custom pellicles. A 5x7" one appears to be only $250.

    Fun to think about...

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