PURPOSE: To automatize an operation by storing a reference sound pressure level, etc., changing a sound pressure level at an each stop position based on a time between releasing actions and changing the stop time based on the changed sound pressure level.

CONSTITUTION: The reference sound pressure level is classified into eight ranks according to the sound pressure. First, the reference sound pressure level is automatically set at four. Next, when a sound pressure level switching button 8 is depressed and two seconds elapses, the rank 6 is displayed on a liquid crystal panel 10. Then, when the time between the release of the last time and the release of the last but one is equal to or below one minute, the reference sound pressure level is made higher by one. When the time is within one to three minutes, the sound pressure level is kept as it is. When it is equal to or above three minutes, the sound pressure level is made lower by one. Thus, the reference sound pressure level is reset so that photographing may be properly performed while viewing whether the past release condition easily holds and the stop time is also reset according to a stop time decision table with the resetting of the level.