Sony HDR-CX360 Operating Manual page 105

If white circular spots appear on photos (HDR-CX360/CX360V/PJ30/PJ30V/
PJ50/PJ50V)
This is caused by particles (dust, pollen, etc.) floating close to the lens. When they are
accentuated by the camcorder's flash, they appear as white circular spots.
To reduce the white circular spots, light the room and shoot the subject without a flash.
Particles (dust, pollen,
etc.) in the air
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