1DX & Mark III focusing with 3rd party lenses

[dswatson83]

After reading some of the details of the new focus systems, it is apparent that the sensitive dual cross type center focus point only works with most f/2.8 and faster lenses. Canon specifies which Canon lenses this will apply to but I wonder if it will also support 3rd party lenses. I typically get all Canon lenses but I have been considering the future Tamron 24-70mm f/2.8 Di VC USD since Canon does not have a stabilized 24-70mm f/2.8. I really want the IS for use with video mostly and it would be nice to shoot indoor at slower shutter speeds. I was wishing the new Canon 24-70 f/2.8 II was stabilized but given the fact that it is not and the outrageous price for a non IS lens, I doubt we will ever see one. Cropped bodies have a stabilized f/2.8 wide zoom and it sucks that Canon has nothing given the use of video. Just wondering if going to a 3rd party f/2.8 lens is going to render the awesome new sensitive dual cross center focus point useless.

 

[Loswr]

Just wondering if going to a 3rd party f/2.8 lens is going to render the awesome new sensitive dual cross center focus point useless.

The Canon 24-70 only activates the center one of the five dual crosses, and that may be the case for the Tamron 24-70 as well.

It's most likely going to depend on how Tamron reverse-engineers (aka spoofs) the AF system. In the past, 3rd party vendors have used lens codes from old Canon lenses as the IDs for their lenses - this got Tamron into trouble previously, when Canon discontinued support for some very old lenses for which newer Tamron lenses used those codes, resulting in off-center cross-type points not functioning properly with those lenses on 40D/50D/60D/7D bodies.

 

[scottcognato]

when Canon discontinued support for some very old lenses for which newer Tamron lenses used those codes, resulting in off-center cross-type points not functioning properly with those lenses on 40D/50D/60D/7D bodies.

That's why if I am having a really hard time justifying the extra $ for an L lens, I buy used. It usually brings the prices into more comparable territory, and I always feel like the an L is a better long term investment than a 3rd party lens. Just my 2 cents, though.

-Scott

 

[dswatson83]

That's why if I am having a really hard time justifying the extra $ for an L lens, I buy used. It usually brings the prices into more comparable territory, and I always feel like the an L is a better long term investment than a 3rd party lens. Just my 2 cents, though.

The Canon lenses are almost always a better long term investment and resale is normally better. However, given that Canon does not and likely will not have a full frame 24-70 f/2.8 IS or anything close to it, this will probably be a popular Tamron lens given that it performs well.