a camera shake amplitude detecting device comprises a mechanical detector for detecting a shake acceleration when a camera body is shaken , and a mechanical shake calculation device for calculating a shake amplitude of the camera body based on the detection output of the mechanical detector . the mechanical shake calculation device discriminates a time point of change between a positive acceleration and a negative acceleration based on the detection output of the mechanical detector , calculates and integration constant , and calculates a velocity by integrating by time the acceleration detected by the mechanical detector . in order to reduce the time required to calculate exact angular velocity , the constitution comprises an angular velocity sensor for detecting a shake of a camera , a high - pass filter for filtering off certain low frequency components of the output from the angular velocity sensor , a switch means for initializing the high - pass filter when the power source is turned on and a control means for detecting the time when the output of the angular velocity sensor becomes equal to 0 and switching the switch means to bring the high - pass filter in the active state .