Olympus OM 10 - Manual (Page 7)

PREPARATIONS BEFORE TAKING PICTURES
The OM-10's circuits
are powered by two 1.5V alkaline-manganese or silver oxide batteries.
Without them, the shutter of this electronic
single lens reflex camera will not function.
This section
is devoted to explaining the preparations
which you must go through before proceeding to take pictures.
Please keep in mind that they are indispensable
for obtaining good results.
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