EOS 5D + extender 1.4 + 100-400 IS L: Will AF work?

Discussion in 'Digital Cameras' started by Lucas, Jan 3, 2006.

  1. Lucas

    Lucas Guest

    Hi all!

    At some rare occasions I could use some extra "reach" on my 5D with
    100-400mm IS L. I probably got a little pampered with the extra "reach" on
    my EOS Rebel (1.6 factor).
    So I was thinking of buying an EF 1.4x II extender.

    By now I found (if I read everything correctly):
    5D-manual: central AF-point will work with lenses with maximum aperture of
    5.6 and larger
    100-400-manual: AF with extender will not work (at all), IS will, MF is
    always possible
    Website Canon USA: the extender can be used on the 100-400

    Since I got a little confused about the AF-thing, I called Canon Support
    Europe (I live in Holland). The nice lady on the telephone was unable to
    help me: "nothing in my books about an EOS 5D: camera is too recent; the
    lens with extender will AF on EOS-1-series bodies though". Sorry, I don't
    own any 1-series.

    BTW: I will not invest in expensive prime telephoto-lenses: for the rare
    occasion they will be used, for me it is not wise to invest in those.

    Any help?


    Lucas, Jan 3, 2006
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  2. Lucas

    This old Bob Guest

    I thought only the 1D and 1DS could AF with a max aperture of f/8.0.
    This old Bob, Jan 3, 2006
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  3. Lucas

    This old Bob Guest

    Sounds like you answered your own question: Max aperture is f/5.6 on the 5D
    so the 100-400 with not AF with the Canon extender (unless you tape over the
    pins, etc.).
    This old Bob, Jan 3, 2006
  4. Lucas

    Lucas Guest


    In my part of the country (Postal Area 45xx, Dutchmen know where this is) no
    shop has the extender in stock (I checked!), so I would have to travel to a
    nearby bigger city, travel at least one hour single trip, take some time to
    test, return home, cost me half a day. Therefore, since there is no
    "oldfashioned shop around the corner" I thought Usenet would be more
    Moreover, not many dealers allow new items that are not sold in numbers to
    be tested, certainly not on customers' camera's. Even the tiniest scratch on
    the mount degrades the value: item is not new anymore. It seems you are
    Dutch as well, you should know how this works over here...

    I do not want to "sit first row for a dime" as you so eloquently stated in
    Dutch, just want to be practical.
    Maybe someone else can answer my question.


    Lucas, Jan 3, 2006
  5. Lucas

    Lucas Guest


    I would expect you are right, I just got confused by other information from
    Canon, and no real help from their Customer Service. Just want to be sure
    about things, hence my posting.

    Lucas, Jan 3, 2006
  6. Lucas

    This old Bob Guest

    Ask in the 5D forum on www.dpreview.com

    This old Bob, Jan 3, 2006
  7. Lucas

    This old Bob Guest

    Yes. Well, not only is the 5D not 1-series camera, but it's not even a 3
    either. :)
    This old Bob, Jan 3, 2006
  8. Lucas

    Gormless Guest

    Well, by that logic all you have to do is crop the 5D pics in PhotoShop by
    the equivalent of a 1.6 factor and you can have your extra reach back.
    Gormless, Jan 3, 2006
  9. Lucas

    Skip M Guest

    I don't have an extender, but as far as I know, it won't work with the 5D.
    It isn't built on the 3 body, it is more like the old EOS5, but not in
    construction, but like the place in the lineup. F5.6 is the max aperture
    for the 5D, according to everything I can find...
    Skip M, Jan 4, 2006
  10. $I don't have an extender, but as far as I know, it won't work with the 5D.

    Officially correct. Unofficially, YMMV; see below.

    $It isn't built on the 3 body,

    Correct. And its AF system is derived from that of the 20D, which
    shares its f/5.6 limitation, as do all other Canon bodies with
    fewer than 45 AF points.

    If you use the 100-400 and Canon's 1.4x, the body will know your
    lens is too slow for AF, and the AF system will not be active.

    If you use a third-party TC which doesn't signal its presence to
    the lens, or if you tape over the three extra contacts (either on the
    lens or on the Canon TC) which are used for the TC to let the lens
    know it's there, the body will still think you have a 100-400/4.5-5.6
    lens, and the AF system will remain enabled. Now, since you're using
    it in a situation for which it was not designed, it may or may not
    work; don't be surprised if it's unreliable, particularly in low
    light or with low-contrast targets.[/QUOTE]
    Stephen M. Dunn, Jan 4, 2006
  11. Lucas

    Mark² Guest

    I don't think the 5D takes after the 3, and I don't think it focuses beyond
    In fact, I'll put $100 on that...save for the taped-contacts trick...
    It's really more like a thicker Elan or 20D than the much larger 3 in terms
    of build/body design anyway, as far as I can tell... But I don't own it! :)
    Mark², Jan 4, 2006
  12. Lucas

    Lucas Guest

    Thanks all for the input; the best info came from 'This old Bob": checking
    the 5D forum on www.dpreview.com.
    There I found all the answers I needed. Thanks Bob!

    Lucas, Jan 4, 2006
  13. Lucas

    MSpn Guest

    I happen to live in the same country. You can travel half the country in one
    hour. How do you travel ? By bike ?

    je overdrijft.
    MSpn, Jan 4, 2006
  14. Lucas

    Lucas Guest

    Dutch: Ik drijf niet over!

    From my place the nearest bigger city would be Goes, that is 50 minutes by
    highway, and then I still would need to find a parking space somewhere. When
    using public transport it would take 1 hour and 25 minutes. I can always try
    going the other way, into Belgium, but that would take 55 minutes plus.
    Do you really live in the same country as me? Doesn't sound like it!

    Dutch again: Kom voor de gein maar eens controleren! Het is hier verdorie
    geen Randstad!

    Lucas, Jan 4, 2006
  15. Lucas

    Skip M Guest

    You don't miss what you never had. The f8 focusing came in with the 3, so
    my 1n didn't have it, nor did my A2. I'm just happy to get spot metering
    back, but it's not linkable to the focus point, so that tempers my joy a
    little. But HOOBOY, it's nice to have a fisheye work as a fisheye and a
    16mm work as a 16mm, not to mention that my 100 f2 is back in business!
    Skip M, Jan 5, 2006
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