Comments on: 5D Mk III AF points and 3rd Party Lenses

By: Stephane

Stephane — Mon, 04 Mar 2013 15:46:13 +0000

which group is the CANON EF 24-70mm f/2.8L II USM

By: Roger Cicala

Roger Cicala — Mon, 07 Jan 2013 18:52:15 +0000

Jon,
I think the Sigma 30mm f/1.4 is it’s predecessors. They haven’t changed that lens in several years.

By: Jon

Jon — Mon, 07 Jan 2013 18:48:52 +0000

Do you guys know if the new Sigma 30mm 1.4 DG does any better than its predecessors?
Thanks for the great post!

By: Deep

Deep — Sat, 05 Jan 2013 19:05:40 +0000

Curiously, the older 28-70 f/2.8 is a group A lens but the 24-70 is a group B lens. I am guessing the 24-70 II is also group A lens (not in the manual, probably because it was released afterwards).

By: Michael C

Michael C — Thu, 20 Dec 2012 01:22:26 +0000

Since some users might try to use the lateral points with a lens that doesn’t allow them to function, Canon has prevented the frustration of not being able to achieve focus when the user expects it.

Is it also possible one reason Canon is doing this is for focusing speed when the user has enabled auto-selection using all focus points? By turning off the focus points that would not function properly with a specific lens attached, the processor does not have to include the signal from those points in its calculations. The less data to process, the faster it will complete the calculation and send instructions to the lens.

By: Andrzej

Andrzej — Sun, 02 Sep 2012 11:49:26 +0000

Great article!

One thing, my Sigma 15mm f/2.8 fisheye (EX DG) shows as group G (and not C). Something wrong/different with mine or mistake in your list?

By: Mike B

Mike B — Tue, 26 Jun 2012 17:19:36 +0000

You have the Sigma 85mm mislabelled – you have it as a 2.8, but it is a 1.4

By: John Thomas

John Thomas — Sat, 23 Jun 2012 06:40:54 +0000

@Steve Runyan: (Double)Cross-Type sensors are much more precise and sensitive in low-light conditions. It can make all the difference between a keeper and a miss when one shoot a photo journal in a low-light event, especially if it is fast-paced.

@Anton: No, not all Canon lenses are “A”. Also, Canon does not limit its AF with 3rd parties. In fact, the main factor isn’t the brand (very big grin) but the iris diameter for each lens. This will determine which AF points will be enabled.

Just my2c & HTH

John Th.

By: Roger Cicala

Roger Cicala — Thu, 21 Jun 2012 22:22:13 +0000

Anton – nobody puts crop lenses on 5DIIs. But I’m assuming Canon’s next crop camera will have this AF system. This way I don’t have to retest.
Roger

By: Anton

Anton — Thu, 21 Jun 2012 21:30:39 +0000

What about Canon lenses? Are they all “A”? Does Canon limits its AF with third party lenses on purpose?
By the way, who puts crop-lenses on 5dmk3?