The M40 is a no frills light meter which just measures the light reflected from objects. There are no complex settings and a very simple mode of operation, which made it an inexpensive first accessory for photographers with their first camera. To use the unit it’s as simple as just pointing it at the subject, pressing the button on the side, so the meter needle measures the light, and then turning the dial, so the green indicator matches the position of the needle. Once the reading has been taken the scale at the bottom of the dial shows the exposure settings to use. There are also EV readings available in a little window at the top of the dial. In working condition and good cosmetic condition.
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