Chromatic aberration compensation function (CAC)

The chromatic aberration compensation function minimizes color smearing in peripheral images. This function automatically compensates for registration error that is caused mainly due to slight chromatic aberration, which is hard to completely compensate with the lens itself, using the camera recorder unit.

When the lens compatible with the chromatic aberration compensation function is mounted, if the camera has the chromatic aberration compensation data of the lens, then the chromatic aberration compensation function is activated automatically.

What is lens chromatic aberration?

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“Chromatic aberration” here refers to zoom factor chromatic aberration. Zoom factor chromatic aberration occurs since the diffraction ratio of a lens differs according to red (R)/green (G)/blue (B). Chromatic aberration on the lens itself is compensated for, but still remains in the periphery, in particular. Also, this chromatic aberration occurs on zoom lens due to a complex relationship between zoom ratio, aperture and focal distance. In image terms, this is registration error.

Chromatic aberration compensation function

To compensate chromatic aberration, store the chromatic aberration characteristics of the lens regarding zoom ratio, aperture and focal distance to the camera recorder beforehand. Connect a lens that matches those chromatic aberration characteristics, and perform compensation matched to the zoom ratio, aperture and focal distance of that lens.

The camera does not store chromatic aberration compensation function data of the lens as a factory setting.

Operation of chromatic aberration compensation function

Operate by the following procedure when lens data is already stored on the camera.

Mount the lens on the camera, and connect the lens connector to the camera.

Set [MENU] → [CAMERA SETTINGS] → [EXT.FUNC] → [CAC] to [ON].

If the lens model number stored on the camera matches the model number of the connected lens, the chromatic aberration data stored on the camera will automatically be read.