# Autofocus at f/8 and Beyond



## mackguyver (Dec 11, 2013)

EOS 60D (using autofocus), 800mm f/5.6 + 1.4x (1120mm (1792mm equivalent)) @ f/8, 1/400s, ISO 100 

How is this possible? The 60D doesn't support AF at f/8, right? 

Here's a little-known secret: While no bodies can autofocus using phase AF beyond f/8, all current bodies support AF in LiveView at any aperture as long as there's enough light to get focus lock. The key is to use a cable release and set your shutter to AF/AE lock. For back-button focus types (like myself), this is something that needs to be changed to work, but for others, the camera is set that way by default.

Once set, put your camera and f/8 lens + extender combination on a tripod. Turn on LiveView and move the AF point to the desired location (the eagle's eye in the example above), then use the shutter button on your cable release to AF and take the shot.


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## privatebydesign (Dec 11, 2013)

There are a couple of other ways too. 

Many third party TC's don't report their existence so the camera doesn't know what aperture it is actually looking through, an added bonus is most of the third party TC's work on many more lenses than the Canon TC's do.

Also there is the famous pin taping, works for most Canon 1.4TC's, put a piece of tape over the leftmost three pins as you look at it when mounted on a body looking at the camera as a subject would. This negates the feedback that tells the body about the one stop hit.


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## surapon (Dec 26, 2013)

THANKSSSS you, Sir, Dear Mackguyver and Privatebydesign.
Thanks for great tricks which I do not know before.
Happy holidays to you.
Surapon


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