Digital cameras are big on sound effects. Some cameras play a little ditty when the camera is turned on, make a beeping sound to tell you about an adjustment, and emit a little shutter sound when you take the picture. These sounds may not be appreciated in every picture-taking setting, though. To quiet your noisy digital camera:
Check your camera’s documentation, such as the manual.
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Make sure your camera allows you to mute (or, at least, turn down the volume on) those sound effects somewhere in its menu.
Find your camera’s sound effects menu option.
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The camera’s documentation can help you here, too.
Make adjustments to the sound effects settings.
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If you can’t mute the camera all together, select the quietest setting available.