This is an unusual and rare 90 degree finder for the FED cameras. It was made in the 1930's by the FED commune.
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The finder allows to compose picture while holding the camera perpendicularly. A pivoted mirrored window (see rear view) makes it possible to use a rangefinder. I believe there was a Leica accessory of this design, and it was copied by the Russians.
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Known serial numbers:
# _________ owner/source ________ remarks
903 _______ eBay
904 _______ A.Berry
1315 ______ David Tomlinson
1812 ______ Avto Metreveli
1967 ______ imcphoto
2053 ______ Fed book (1939)
2404 ______ Communist cameras
2993 ______ ebay _______________ leather case, photos 2, 3, 4
3672 ______ eBay
3957 ______ David Tomlinson
3991 ______ ebay
4453 ______ Michel's coll. _________ with box
5456 ______ eBay
6032 ______ Christian G. (Niko80)
6108 ______ Avto Metreveli
6171 ______ Fedka.com
6682 ______ Fotomuda
7010 ______ SovietCams
7555 ______ eBay
7740 ______ eBay
8138 ______ eBay
8516 ______ Michel's coll. _________ incomplete
8749 ______ Michel's coll.
8789 ______ Leica shop
9256 ______ eBay
9263 ______ eBay
9758 ______ eBay
9884 ______ eBay
9987 ______ eBay
10495 _____ geoffox23
10778 _____ Westlicht auction#29 lot#257
11182______web
11208______web
11623 _____ Molotok
11992______web
12077 _____ Chris Sabine
12145 _____ eBay
12358 _____ eBay
13362 _____ eBay
13484 _____ eBay
13594 _____ eBay
14718 _____ eBay
14838 _____ PYC
14909 _____ Jacques M.
15662 _____ eBay
15981 _____ eBay
16016 _____ eBay
100411 ____ PYC ____________ # confirmed, one digit seems to be doubled
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