Autofocus reality revisited: How does the Canon EOS 6D measure up?

by Roger Cicala

posted Friday, November 30, 2012 at 8:57 PM EDT

A few months ago we published a series of articles showing that certain Canon lenses on the newest Canon cameras -- the EOS 5D Mark III and EOS-1D X -- autofocused more accurately than on earlier Canon bodies for center-point, single-shot autofocus. These combinations actually offered similar autofocus accuracy to that we could obtain with Live View.

To emphasize, though, we’re only testing AF with the center AF point, and for still shots in a lab. Servo mode, zone focus, etc. don't enter into the equation.

With the EOS 6D now being released we had, oh... about 6,593 people ask us if the autofocus system was as accurate as the 5D Mark III, or more like that of the 5D Mark II. Obviously the 6D doesn’t have the whiz-bang 61 point autofocus system of the Mark III, which features 41 cross-type points. Instead, it has 11 points, with only one cross-type. But people still hoped that the center point might be supercharged.

Now, I’m rather cynical, and was pretty certain that the intro level camera was not going to get a top level AF system, but when LensRentals' first dozen EOS 6D bodies came in today it seemed like an easy thing to check. For those of you who aren’t in the loop, the previous Canon cameras' test results are here.

We used exactly the same methods as before, and shot with a 28mm f/2.8 IS lens, since we knew that was one capable of the more precise autofocus. We repeated the test on two cameras, using two lenses for two runs. All were identical, and a typical run is shown below. Live View results are in blue, while standard phase detection is in red.


As we did with the other tests, we compared the standard deviation of the Live View shots (10) to the phase detection AF shots (28).

The bottom line is that the EOS 6D's phase detection autofocus system is about identical to that in the 5D Mark II, at least in terms of center point accuracy. It may be worlds better in low light, Servo mode, or with peripheral sensors; I can’t comment on that. And even if it doesn't rival that of the 5D Mark III, I actually didn’t find the EOS 5D Mark II's center point autofocus bad at all.

(Roger Cicala is the founder of Visit to check out that cool lens you've been hankering for, and for some of the best customer service on the Internet!)