Kodak Kodalux* Selenium Light Meter - Retina Camera - Gossen Germany F*S
This Eastman Kodak Kodalux light meter was made by Gossen, it's intended for Kodak Retina cameras but it would fit on anything with an accessory shoe. I bought this in 1967 to use on my Leica M2.
Simple enough to operate: there's a knob on the back turns an internal cylinder in the meter face. The cylinder is painted with stripes, and a different stripe shows depending on what position the knob is in. This is geared to another drum that has ƒ/stops. You aim the meter and turn the knob until the little stripe is underneath the needle, and then read the combinations on the right-hand side.
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