An optical apparatus including an imaging apparatus and a lens apparatus
each having a communicating portion performing communications is
disclosed. The optical apparatus is provided with: an imaging optical
unit; a memory in which information of an optical performance of the
imaging optical unit is stored; an image pickup device imaging a subject
image from the imaging optical unit; an imaging controller changing an
information size of image information from the image pickup device; and a
lens controller connected to the imaging controller through the
communicating portions and performing communications with the imaging
controller. The lens controller takes out the information of the optical
performance from the memory in response to an instruction from the
imaging controller, and transmits the information to the imaging
controller through the communicating portions. The imaging controller
changes the information size of the image information in accordance with
the information of the optical performance from the lens controller.