The invention includes an image sensor, a shutter which opens/closes by
making a front curtain and a rear curtain travel, a light source which
illuminates the image sensor, a control unit which performs control to
make the front and rear curtains travel with a predetermined time shift
to form a slit-like opening, and to make the light source emit light a
predetermined period of time after the start time of traveling of the
front and rear curtains, a detection unit which detects the deviation
between the position of an image of the recorded slit-like opening and a
predetermined reference position, a computation unit which calculates the
error between the traveling start timing of the front and rear curtains
on the basis of the detected deviation, and a correction unit which
corrects the calculated error between the traveling start timing of the
front and rear curtains.