AF Modes: Differences between One-Shot AF, AI Servo AF, and AI Focus AF (EOS 5DS / EOS 5DS R)
18-May-2015
8202601800
Solution
You can select the AF operation characteristics to suit the shooting conditions or subject. In the [ 
] mode, "AI Focus AF" is set automatically.
] mode, "AI Focus AF" is set automatically.1. Set the lens focus mode switch to [AF].
2. Set the camera's power switch to [ON].
3. Set the Mode Dial to [ P / Tv / Av / M / B ].
4. Press the [ DRIVEć»AF] button.
5. While looking through the viewfinder or at the LCD panel, turn the [ 
] dial to select the AF mode.
] dial to select the AF mode.- ONE SHOT : One-Shot AF
- AI FOCUS : AI Focus AF
- AI SERVO : AI Servo AF
NOTE
In the [P], [Tv], [Av], [M], or [B] mode, AF is also possible by pressing the [AF-ON] button.
Suited for still subjects. When you press the shutter button halfway, the camera will focus only once.
- When focus is achieved, the AF point which achieved focus will flash briefly in red, and the focus confirmation light [
] in the viewfinder will also light. - With evaluative metering, the exposure setting will be set at the same time focus is achieved.
- While you hold down the shutter button halfway, the focus will be locked. You can then recompose the shot if desired.
NOTE
- If focus cannot be achieved, the focus indicator [ ] in the viewfinder will blink. If this occurs, the picture cannot be taken even if the shutter button is pressed completely. Recompose the shot and try to focus again or see Difficult subjects for AF (Auto Focus) (EOS 5DS / EOS 5DS R).
- If [
Beep] is set to [Disable], the beeper will not sound when focus is achieved. - After achieving focus with One-Shot AF, you can lock the focus on a subject and recompose the shot. This is called Shooting with Focus Lock (EOS 5DS / EOS 5DS R). This is convenient when you want to focus on a peripheral subject not covered by the Area AF frame.
This AF mode is for moving subjects when the focusing distance keeps changing. While you hold down the shutter button halfway, the subject will be focused continuously.
- The exposure is set at the moment the picture is taken.
- When the AF area selection mode is set to 65-point automatic selection AF, focus tracking will continue as long as the Area AF frame covers the subject.
NOTE
With AI Servo AF, the beeper will not sound even when focus is achieved. Also, the focus indicator [ ] in the viewfinder will not light up.
] in the viewfinder will not light up.AI Focus AF switches the AF mode from One-Shot AF to AI Servo AF automatically if the still subject starts moving.
After the subject is focused in One-Shot AF, if the subject starts moving, the camera will detect the movement, change the AF operation automatically to AI Servo AF, and start tracking the moving subject.
NOTE
When focus is achieved with AI Focus AF with the Servo operation active, the beeper will continue beeping softly. However, the focus indicator [ ] in the viewfinder will not light up. Note that focus will not be locked in this case.
] in the viewfinder will not light up. Note that focus will not be locked in this case.