Rear of Camera Controls

As mentioned earlier it's round the back where the differences between the Mark III and its predecessor are most striking. The larger screen means that the column of buttons down the left side of the LCD on the Mark II has gone and the remaining buttons moved around a little. You also get a SET button and new multi-controller (as seen on the EOS 40D).

Left side of camera rear (above and below LCD monitor / LCD status panel):

Button / mode Shooting Mode Play Mode
Enter / Leave the Menu

The camera menu is described on the following pages of this review. Use the Quick Control Dial to move up and down menus and the front dial to move between menu pages. You can also use the multi controller to do the same thing (left-right: menu pages, up-down: menu items).

Displays current camera settings / information - two different modes are available (changed using CF II-9). In Live view mode changes the type and amount of information displayed as an overlay.

Press to change the type and level of information shown along with the image.

Displays the last image taken (or the last image on the card).
Exit Play Mode

Return to shooting mode. The Mark III is a shooting priority camera, which means that no matter what is displayed on the rear LCD this will be canceled if any of the camera's photographic functions (example half-pressing the shutter release or AF-ON) are accessed.

During record review press to erase the displayed image, displays an OK / Cancel dialog.

Press to erase the current image, displays an OK / Cancel dialog.
FUNC. White Balance,
Image Size/Quality
Record Func + Media Folder Select

Cycles through three pages of commonly used settings (some of which have been moved here due to the loss of dedicated buttons in the redesign of the body).
No function
Picture Style

Displays the Picture Style selection / adjustment screen.
Protect / Voice Memo

Displays the Picture Style selection / adjustment screen.

Right side of camera rear:

Button /
Auto focus start

The AF-ON button allows you to trigger auto focus independently of the shutter release 'half-press'. Note that you can re-program the exact function of the AF-ON button via C.Fn IV-1 or you can switch the AF-ON button and AE/AF lock button via C.Fn IV-2 (all custom functions detailed in the menus section of this review).

If in single view play mode, pressing this button will switch to a 2x2 thumbnail index, press again for a 3x3 index. If already magnified pressing this button reduces magnification level.

Press to magnify the current image, there are fifteen steps up to a maximum magnification of 10x. Once magnified you can use the multi-controller to move around the image. In Live View mode this button jumps between 1x, 5x and 10x magnifications


The multi selector has three main uses:
Record Mode: Select Focus point (when metering is active)
Record Mode: Select Center Focus point by pressing
Record Mode (Live View): Select Focus point
Play Mode: Scroll around the image in magnified view

The Multi-selector is also used to navigate menus.

Quick Control Dial

By default (with the power switch in the third position, one step past ON) the Quick Control Dial can be used to change exposure compensation (steps depend on C.Fn I-1). C.Fn IV-3 allows you to change this to control ISO or AF point selection.

It is also used to navigate menus and to change Shutter Speed value in Manual mode (though you can switch the front and rear dials using C.Fn IV-5.

SET button

If Live View is enabled pressing SET enters or leaves live view mode otherwise this button by default has no function in shooting mode, however it can be configured to one of seven different functions via C.Fn IV-4.

Vertical / Portrait hand grip

The Mark III has an integrated vertical hand grip which runs the length of the base of the camera. There are a number of controls repeated on the vertical grip (in addition to the shutter release): main dial, FEL button, AE Lock button, AF Assist button and the AF point selection button. These controls are normally disabled and can be enabled by turning the vertical grip activation switch (great name) to 'ON'.

Depth-of-field preview

At the front of the camera beside the lens mount (hand grip side) is the Mark III's depth-of-field preview button. Press this with a small aperture selected (or metered) and the lens will 'stop down' to that aperture allowing you to preview the effective depth of field of the final shot.