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- Chromatic aberration compensation function (CAC)

# 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?

“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 following four types of chromatic aberration compensation function data for lenses are stored to memory before the camera is shipped.

Indicated Compatible Lens Part No. on Camera | Indicated Compatible Lens Part No. on Camera
--- | ---
HA16X 6.3BERM-M58 | HA16x 6.3BERM-M58
HA22X 7.8BERM-M58 | HA22x 7.8BERM-M58
HJ17EX 7.6B IASE | HJ17ex 7.6B IASE
HJ22EX 7.6B IASE | HJ22ex 7.6B IASE

NOTE

- For details on additions and modifications to lenses compatible with the chromatic aberration compensation function, visit the support desk at the following website:

  https://pro-av.panasonic.net/

## 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 [ON] in the main menu → [MAINTENANCE] → [CAC ADJ.] → [CAC CONTROL].

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

## Viewing the operation status of chromatic aberration compensation function

Push the <MARKER SEL>/<MODE CHECK/MENU CANCEL> switch towards the <MCK/MCL> side with the menu not displayed in the viewfinder screen.

If the letters [CAC] are displayed at the top right of the viewfinder screen, the chromatic aberration compensation function is in operation.

If the letters [CAC] are not displayed, the chromatic aberration compensation function is not in operation.

Set [ON] in the main menu → [VF] → [VF INDICATOR] → [CAC].

The letters [CAC] are displayed at the top right of the viewfinder screen.

[ON] is set in the factory settings.

## Loading the chromatic aberration compensation file from the SD memory card

Fig. 1

Fig. 2

Insert the SD memory card written with the chromatic aberration compensation data you downloaded from out website into the camera.

For details on downloading, refer to the following website.

https://pro-av.panasonic.net/

Select [LOAD] from the main menu → [FILE] → [CAC FILE (SD CARD)]. (Fig. 1)

The list of CAC files on the SD memory card is displayed.

Select the file number to load, and press the jog dial button (or <SET> button). (Fig. 2)

The confirmation screen is displayed.

Select [YES], and press the jog dial button (or <SET> button).

The list of CAC files saved in camera memory is displayed.

Select the file number to save, and press the jog dial button (or <SET> button).

The confirmation screen is displayed.

Select [YES], and press the jog dial button (or <SET> button).

The CAC files are loaded to camera memory.

To store two or more chromatic aberration compensation data to the camera, repeat steps 2 to 6.

To end menu operations, press the <MENU> button.

The setting menu disappears, and the camera status display is returned to.

NOTE

- Up to 32 files can be loaded to the camera.

  To load a new file, delete any file before loading the new file.

  For details, refer to “Deleting the chromatic aberration compensation file from the camera”.

## Deleting the chromatic aberration compensation file from the camera

Set [OFF] in the main menu → [MAINTENANCE] → [CAC ADJ.] → [CAC CONTROL].

At [LIST/DELETE], use the jog dial button (or <SET> button) to select the lens model number to delete.

The confirmation screen is displayed.

Select [YES], and press the jog dial button (or <SET> button).

The file is deleted.

## When the chromatic aberration compensation data is not functioning properly

When the chromatic aberration compensation function is not functioning properly, or when the chromatic aberration compensation data could not be loaded normally, the viewfinder displays an error message.

Error message | Meaning | Remedy
--- | --- | ---
[CAC FILE DATA NOT FOUND] | There is no chromatic aberration compensation data matching the connected lens when the chromatic aberration compensation function is [ON]. This is displayed when the camera is turned on. | Load chromatic aberration compensation data matching the connected lens to the camera.
[CAC LENS DATA INVALID] | The response data from the lens is not supported, or the response contains information other than that defined in the chromatic aberration compensation data. | The lens is not a lens compatible with the chromatic aberration compensation function. The chromatic aberration compensation will not function, but will not cause any problems in use.
[LENS INIT. NOT COMPLETED] | Position detection (focus zoom) of the lens is encoder type, and initialization is not completed. | Turn the focus/zoom ring to pass through the center of the operating range.

NOTE

- When mounting lens optical system accessories (converter lens attachments), the chromatic aberration compensation function sometimes does not function properly since the optical characteristics of the lens change. In this case, set the chromatic aberration compensation function to [OFF].

- When a focus servo is used on CANON lenses, enable recording after initialization is completed in the automatic initialization mode. Data is sometimes recording while the focus ring is moving.

- When an error message is also not displayed while the chromatic aberration compensation function is not functioning, the software version of the lens might be old. Contact the manufacturer of the lens you are using.

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