SURVEYING DEVICE

A surveying device configured to perform a survey by tracking, as a survey target, a prism attached to a camera of a movable imaging device includes an electronic distance meter configured to measure a distance to the survey target; a horizontal angle detector and a vertical angle detector each configured to measure an angle; a main body supporting these members; a time obtainer configured to obtain a GPS time from a GPS satellite; a tilt sensor configured to detect a posture of the main body a calibrator configured to calibrate the tilt sensor and a survey controller that causes the calibrator to perform calibration during a period in which the time obtainer obtains the GPS time, as an advance preparation to be performed before the measurement.