This exposure meter Revue S110 was sold by Foto-Quelle. It works with a selenium cell and does not require a battery. It is likely from the late 1960s. The displayed light intensity is set on the outer ring. In the photo it is 4. The sensitivity is set on the disk with the small window. In the example ASA 100. The matching aperture and shutter speed values can now be read. The aperture values go up to 45. I've never seen that before. On the back there is a small screw for zero point adjustment. There is no more. It still works. Switzerland, Nov 15, 2021.
Kecko
CC BY 2.0
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