Canon EOS 5DS R Instruction Manual - Page 122

3 Customizing AF FunctionsN One-Shot AF release priority You can set the AF operation characteristics and shutter-release timing for One-Shot AF. : Focus priority The picture will not be taken until focus is achieved. Effective when you want to achieve focus before capturing the shot. : Release priority Priority is given to the timing of shutter release instead of achieving focus. This gives priority to capturing the image rather than achieving correct focus. Note that the picture will be taken even if focus has not been achieved. 122