Switching the Focusing Distance Range
![](/library/CANON/CITS_TECH_SUPPORT/Camera/Lenses/EF%20400mm%20F4%20DO%20IS%20USM/FocusingDistanceRange.png)
You can set the focusing distance range to 3.5 m/11.5 ft. to infinity or 8 m/26.2 ft. to infinity.. By setting a suitable focusing distance range, the actual autofocusing time will be shorter.
![](/library/CANON/CITS_TECH_SUPPORT/Camera/Lenses/EF%20400mm%20F4%20DO%20IS%20II%20USM/warning.png) |
If you autofocus outside the set focusing distance range, the lens may stop focusing at the start of the focusing range; however, this is not a malfunction. Press the shutter release button halfway again. |