Patent ID: 8259216
Filing Date: 2012-09-04
Classification: G02B,G03B,H04N

Abstract:
1. A camera system including a lens unit and a camera body, one of which is removable and attachable from/to the other, wherein the lens unit comprises: an optical system for producing an image of a subject; a focusing mechanism for performing a focusing operation by changing a subject distances with at least a portion of the optical system driven continuously; a first computing section for acquiring shooting parameters as the focusing operation is performed; and a storage section that stores reference data for use to correct focus positions according to a contrast of a video, the reference data being defined by a combination of any of two or more assumed AF frequencies for use to measure the contrast and any of the multiple shooting parameters, and wherein the camera body comprises: an imaging device, which receives the subject's image and outputs a video signal representing the subject's image; and a second computing section for measuring a contrast of the video of the subject based on an evaluated AF frequency proper to the camera body, which is determined in advance, during the focusing operation and calculating a correction value based on the shooting parameter and the reference data associated with a highest contrast, and wherein the focusing mechanism changes the focus positions according to the correction value.