Does Autofocus Work at F-Stops Higher than f8?
You will sometimes hear that teleconverters and some very long lenses result in minimum apertures greater than f5.6 and thereby disable autofocus. This is true for most cameras, though some can still autofocus at f8.
The important thing to know is that this does not mean setting an f1.8 capable lens to f11 will disable your AF. The camera focuses using the widest aperture available and then stops down to take the image.
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