A silver-oxide battery (IEC code: S) is a primary cell with a very high energy-to-weight ratio. They are available in small sizes as button cells, where the amount of silver used is minimal and not a significant contributor to the product cost.
This portable light meter is very useful when used with film cameras without a functional light meter built in. This new version includes aperture priority mode as well as shutter priority mode.
Product Type : Top mounted light meter Angle of detection : 30 degrees ( Similar to 70 – 90 mm focal length lens field of view ) Metering component : Photoelectric Meter Iso detection range : ISO 25 – ISO 1600 Aperture Adjustable Range : f1.4 – f25 Battery Built In : Lithium Batt Weight : 22g plus minus Dimension : 35mm W x 39mm L x 18mm H