Manual Focus (Mf) - Canon ULTRASONIC EF400mm f/2.8L IS III USM Instructions Manual

8. Manual Focus (MF)

When shooting images using manual focus (MF), you can select the manual focus speed.
Use the manual focus speed switch to select a manual focus speed.
Speed is fastest at 1, with 2 and 3 being progressively slower.
Manual focus speed
switch
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