39Preparing the LensIn-Camera Lens CorrectionDepending on the characteristics of the lens used, the corners of an image frame may be darker than the centerdue to light fall-off (peripheral illumination drop), color shift/color fringing may be visible along high-contrastedges in the image (chromatic aberration), or the image produced may not be as sharp at certain apertures (lensdiffraction). In CAMERA mode, you can apply a correction to compensate as necessary. To apply peripheralillumination or chromatic aberration correction, correction data for the lens used is necessary. Automaticchromatic aberration correction is available for broadcast lenses compatible with L.C.A.C.Chromatic aberration and diffraction correction are not applied to RAW recordings but will be applied to proxyclips recorded simultaneously with RAW clips.1 Attach the lens you want to use and turn on the camera in CAMERA mode.2 Select > [v Camera Setup] > [Periph. Illum. Corr.], [Chromatic Aberr. Corr.] or [DiffractionCorrection].• If correction data is not available, [Periph. Illum. Corr.] or [Chromatic Aberr. Corr.] will appear grayed out. Visityour local Canon website and check if there is correction data available for the lens you are using. If so,download the necessary update package, update the camera’s firmware version and repeat the procedurefrom the beginning.3 Select [On].• The camera will apply the correction for the attached lens to all future recordings.NOTES• About in-camera lens correction data: The camera contains a register of correction data for compatible lensesthat were available at the time the camera went on sale. Correction data for future lenses will be madeavailable as part of the regular updates released for the camera’s firmware. For more details, visit your localCanon website.• Peripheral illumination/chromatic aberration correction cannot be applied in the following cases:- When the appropriate correction data is not available for the lens attached.- When using non-Canon lenses. Even if the corresponding menu setting is available (not grayed out), settingit to [Off] is recommended.• Diffraction correction cannot be applied when the camera cannot obtain the current aperture value of the lens.• When peripheral illumination/diffraction correction is activated:- Depending on the recording conditions, noise may appear in parts of the image.- The level of correction will be lower for lenses that cannot provide distance information.- The level of correction will be lower the higher the ISO speed/gain setting used.- When using EF-S lenses, peripheral illumination fall-off may be more pronounced.
