Canon 5D Mark III Optics

Lens Corrections
The Canon 5D Mark III usually ships without a standard "kit" lens, so this section would normally be left blank, however it's sometimes bundled with Canon EF 24-105mm f/4L IS USM lens. While we didn't shoot our usual "kit" lens shots here, we felt that the 5D Mark III's new in-camera lens corrections deserved special mention. See below...

Chromatic Aberration Correction. The 5D Mark III is the first Canon DSLR to incorporate automatic in-camera lateral chromatic aberration reduction.

CA Correction is optional and the system is database driven, so only recognized Canon lenses will be corrected properly. The camera contains correction data for about 25 lenses, and you can register correction data for unregistered lenses using Canon's EOS utility. The default setting is Enabled. As you can see, it worked very well with our Canon EF 24-105mm f/4L IS USM lens, removing most of the color fringing while maintaining good edge sharpness.

Peripheral Illumination Correction. The Canon 5D Mark III also offers Peripheral Illumination Correction to reduce the effects of corner shading found in most lenses when shot at wide apertures. This feature has been available for almost four years now, first offered on the Canon EOS 50D.

Mouse over links above to see how well it corrects the 24-105mm at f/4 and 28mm. The camera contains correction data for about 25 lenses, and you can register correction data for unregistered lenses using Canon's EOS utility. Again, the default setting is Enabled. As you can see, corners and edges are brighter while the center remains at the same brightness when correction is enabled.

Distortion Correction. In addition to Chromatic Aberration and Peripheral Illumination Correction, the Canon 5D Mark III offers Distortion Correction, but only as an option during in-camera raw processing. The camera can't correct for distortion "on-the-fly" like it can for chromatic aberration and corner shading. Since it's a post-processing option, we don't have an example here.

Accuracy
Excellent accuracy from the optical viewfinder and LCD in Live View mode.

The Canon EOS 5D Mark III's optical viewfinder accuracy is excellent, showing essentially 100% coverage with practically no offset or tilt. A noticeable improvement over the 5D Mark II. Live View mode accuracy using the LCD monitor is also excellent, with just over 100% coverage (the captured image shows just a bit less than the monitor.)