Imaging apparatus and method of controlling the apparatus

An imaging apparatus comprising:

• an imaging device;
• a lens which collects light on said imaging device, and forms an image;
• an initial focal point detecting unit configured to detect a positional relationship between said imaging device and said lens to specify an initial focal point which is a focal point found when an exposure start instruction is received from a user;
• a shift pattern determining unit configured to determine a shift pattern of the focal point, such that the focal point in an exposure time moves from the initial focal point, passes through both of a nearest end and a farthest end of a predetermined range of focus at least once, and returns to the initial focal point, the initial focal point being specified by the positional relationship (i) determined by said initial focal point detecting unit, and (ii) observed between said imaging device and said lens;
• and
• a shift control unit configured to move one of said imaging device and said lens based on the shift pattern determined by said shift pattern determining unit, such that the focal point moves from the initial focal point as soon as exposure starts, and arrives at the initial focal point again as soon as the exposure ends.