Canon 1D X Loses Autofocus When Max Aperture Smaller than f/5.6

Canon’s new 1D X is an impressive fusion of the old 1D and 1Ds lines, boasting state of the art sensor quality combined with impressive speed, but there’s one downside that may be a big disappointment to some photographers: the camera loses autofocus when used with lenses with a max aperture of f/8.

While there aren’t any Canon lenses that naturally have an f/8 maximum, adding a 1.4x extender to a f/5.6 lens or a 2x extender to a f/4 lens results in a lens with a max of f/8. If you’re planning on upgrading to a 1D X but need extended reach (e.g. you do bird photography), you may need to shell out some extra cash for a faster lens.

(via Arthur Morris via The Digital Picture)

  • Joakim Fjeldli

    Um.. are you sure this applies to LENSES? Because it’s commonly known that if your aperture is smaller than 5.6 using teleconverters/extenders, you lose autofocus…

  • Patti B

    This isn’t new at all.

  • Michael Zhang

    The previous 1D and 1Ds DSLRs could autofocus at f/8. The 1D X has more autofocus points (61 vs 45), but autofocus is lost past f/5.6:

  • Joakim Fjeldli

    Very well, I stand corrected. This will just “level” it down to other cameras such as the 5D….

  • Abc

    What a silly article. It’s in the same vain as when the iPhone was introduced… “The iPhone will never work, imagine using it after a greasy KFC…”

  • J Yardley

    Actually that is a major issue! I use converters on a regular basis and very much appreciate the ability to retain autofocus on my 1 series bodies when my 5D will not do it. Very good reporting.

  • Nic

    If you use converters and use a lens that slow ‘J Yardley’… then i doubt you will be buying a 1dx… Buy some better glass or use a body that matches your lens choice.

    This is a professional level camera. It therefore assumes you won’t be using consumer glass. 

  • Charles Mason

    canon’s 800mm and 1200mm lenses are hardly “consumer”…

  • Stefan Heymanns

    I don’t think you would call a 500mm f/4 a “consumer” lens.  While in the past you could use a 1D/1Ds with the 500mm + 2x, you can no longer do that with the 1DX.

  • J Yardley

    I use many L class lenses (some of which are F4 or slower to start with). My faster telephotos (like my 200mm F2) are big and heavy and frankly a bitch to carry around. I can pop on my 300mm F4 lens with a 2x adapter and walk for miles. Either way, it’s good to know what a camera is capable of.

    “Let’s go with ‘Poor assumptions for 800′ Alex.”

  • Darren South

    This is a fail for a 1 series camera!

  • Danielgballard

    Fail? Not in my opinion. I’d still make great use of it without
    auto focus. I’m thinking that it’s most likely given use of a converter your distance to
    subject is so far out you can just go with infinity, and not have an
    issu anyway. 

  • zf

    “such as the 5D….”

    Sorry.. 5D? Really? 5D is the worst of the worst AF in the world today. I mean, it use the exact same AF that can be found in 550D 600D(rebels) etc. Even D3100 is better by a high margin. 

  • Ben Jacobsen

    I’m wondering if this is some sort of confusion between a base spec and the math done when using a TC?  If you tape the pins on a 5Dii it’ll AF (or try to at least) in situations where it shouldn’t…  I find it very hard to believe canon would finally deliver a new 1 series that’s both speed and resolution and NOT let their long lens customers take advantage.  Plus, the 1Dx goes down to -2EV for low light shooting, this aperture limit basically deals with that same limit (getting enough light to the AF sensors) so it’s weird that spec would improve but it can’t use a f/8 lens….

  • AC

    If I remember, couldn’t you tape down some of the gold pins on the lens to “fake” autofocus on their lens to work past f/5.6?  I know some people did it for their teleconverters, maybe it could work for the 1D X?    Or maybe… a firmware update ;)

  • Anonymous

    Wait. So that means I have to focus the lens myself? THAT SOUNDS AWFUL.

  • Bobill Weaver

    Canon’s most recent firmware update (qDX -1.1.1 gives the 1DX the capability to autofocus at f/8. I now can achieve autofocus when I add a 1.4X extender to my 800 mm f/5.6, and 100 – 400 mm lenses and when I add a 2X extender to my 300 mm f/4 lens.

  • Bobill Weaver

    Not correct – my 1DMKIV will autofocus with a 1.4X extender attached to my 100 – 400 f/5.6 and my 300 f/4 lens.