Pentax P5 - Main Switch and Shutter-Release Button

MAIN SWITCH AND SHUTTER-RELEASE BUTTON
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• Main switch
To release the shutter, be sure to set the main switch to ON. When
the switch is set to OFF, the shutter cannot be released.
• Shutter-release button
As you set the main switch to ON and depress the shutter-release
button halfway, the meter will be switched on. As you continue
to depress the button, the shutter will be released. Since the meter
has the timer switch, it will automatically be switched off about
ten seconds after you release your finger off the shutter button.