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- Mounting and adjusting the lens
- Chromatic aberration compensation function (CAC)

# Chromatic aberration compensation function (CAC)

The chromatic aberration compensation function minimizes color smearing in peripheral images. The registration error that is caused mainly due to slight chromatic aberration that cannot be completely compensated by the lens is automatically compensated by the camera.

The chromatic aberration compensation function will automatically start to operate when a chromatic aberration compensation function compatible lens is mounted.

## 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

Mount the chromatic aberration compensation function compatible lens to compensate the chromatic aberration. The chromatic aberration compensation function will automatically operate. Or, store the chromatic aberration characteristics of the lens regarding zoom ratio, aperture, and focal distance to the camera 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.

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 in following steps when a chromatic aberration compensation function compatible lens is mounted to the camera.

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

Set to the [CAMERA] menu → [CAC ADJ.] → [CAC CONTROL] → [ON].

The chromatic aberration compensation data is read from the lens and the chromatic aberration compensation function will operate automatically when the camera is turned 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 on a preferential basis.

## Viewing the operation status of chromatic aberration compensation function

Push the <MARKER SEL>/<MODE CHECK> switch towards the <MCK> 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 to the [VIDEO OUT/LCD/VF] menu → [INDICATOR] → [CAC] → [ON].

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

This is set to [ON] as the factory setting.

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

[EXIT]

[CAMERA]

[MENU]>[OTHERS]>[FILE]>[CAC FILE(SD CARD)]>[LOAD]

[EXIT]

[EXIT]

[FILE]

[LOAD]

[SCENE FILE]

[SCENE FILE(SD CARD)]

[AUDIO]

[BATTERY]

[SETUP FILE(SD CARD)]

[DELETE]

[VIDEO OUT/LCD/VF]

[GENLOCK]

[SETUP FILE(MEMORY)]

[RECORDING]

[COLOR BARS]

[CAC FILE(SD CARD)]

[NETWORK]

[LED]

[LENS FILE(SD CARD)]

[LENS FILE(MEMORY)]

[CLOCK]

[SYSTEM]

[OTHERS]

[GPS]

[SLOT FOR LOAD/SAVE]

Fig. 1

Fig. 2

Insert the SD card with the chromatic aberration compensation data that was downloaded from our website into the card slot of the camera selected by the [OTHERS] menu → [FILE] → [SLOT FOR LOAD/SAVE].

For details on downloading, refer to the following website.

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

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

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

Select the file number to load. (Fig. 2)

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

Select the file number to save.

A confirmation screen is displayed.

Select [SET].

The CAC files are loaded to camera memory.

To store multiple chromatic aberration compensation data in the camera, repeat steps 2 to 5.

Press the <MENU> button to close the menu.

The menu is cleared and returns to the camera status display.

NOTE

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

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

## Deleting the chromatic aberration compensation file from the camera

Set to the [CAMERA] menu → [CAC ADJ.] → [CAC CONTROL] → [OFF].

Select the lens model number to delete with [LIST/DELETE].

A confirmation screen is displayed.

Select [SET].

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 is not loaded normally, an error message is displayed on the viewfinder.

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 enabled. 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 INITIALIZATION 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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