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Thread: what cause lenses to "hunt" during AF ?

  1. #1
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    Default what cause lenses to "hunt" during AF ?



    sometimes, even a f1.4 lens !

  2. #2
    Senior Member Kit's Avatar
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    Default Re: what cause lenses to "hunt" during AF ?

    when you pay so much for a lens, of course it has to be working even when it cannot find anything to focus on mah.....

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    Default Re: what cause lenses to "hunt" during AF ?

    Low lighting, a bright object with no visible details on it, a large plain surface or distance between u and yr subject can cause lens to hunt. The latter being slower to focus lock.
    Canon EOS 5D, 24-70 f/4 L IS, 50 f/1.2 L, 70-300 f/4-5.6 L IS, 600EX-RT. Sigma 12-24 f/4.5-5.6 EX.

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    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by Kit View Post
    when you pay so much for a lens, of course it has to be working even when it cannot find anything to focus on mah.....
    If you have nothing constructive or instructive to say, I suggest you shut up. The man who only shoots stationary buildings has no right whatsoever to be sarcastic in such discussions. Keep your arrogant criticisms to yourself.

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    Senior Member Kit's Avatar
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    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by thw View Post
    If you have nothing constructive or instructive to say, I suggest you shut up. The man who only shoots stationary buildings has no right whatsoever to be sarcastic in such discussions. Keep your arrogant criticisms to yourself.
    I'm shivering with fear........... bite me..

  6. #6

    Default Re: what cause lenses to "hunt" during AF ?

    i have tat same problem at times... esp in low light n sometimes when shooting closeup shots.. think i move too close... closer than my min focusing dist..
    Trust me, I'm not so bad! | TangShooters

  7. #7

    Default Re: what cause lenses to "hunt" during AF ?

    yes, kit often has nothing much to say
    just passes snide comments
    and ignores comments on his own photography threads

    probably has an overly high opinion of himself, been there seen that
    some people just have an overblown ego, let it go guys

    must say here that it's a very sad existence though, to just troll around and float on clouds which are self-constructed, boohoo


    in any case, on topic - it depends on a lot of things, whether the object is moving
    whether the object has "contrast"

    if you try to af on a white smooth surface even your 20,000 dollar lens will not be able to find anything la

  8. #8
    Senior Member Kit's Avatar
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    Default Re: what cause lenses to "hunt" during AF ?

    I guess watching dot magnified 1000 times and bitchin' must have given some a really exciting existence then......

  9. #9

    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by Kit View Post
    I guess watching dot magnified 1000 times and bitchin' must have given some a really exciting existence then......
    what's wrong with you

    if anything, most people here would vouch that i'm the antithesis of that
    i use cheap lenses, and don't really care that much about equipment

    AF has nothing to do with equipment, and people are just trying to learn something
    understanding one's equipment and its limitations is the key to breaking past all that
    so why limit them and paint everyone with the same brush?

    i doubt the ts is like that, same goes for most of the ppl who have been posting here

  10. #10
    Senior Member Kit's Avatar
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    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by night86mare View Post
    what's wrong with you

    if anything, most people here would vouch that i'm the antithesis of that
    i use cheap lenses, and don't really care that much about equipment

    AF has nothing to do with equipment, and people are just trying to learn something
    understanding one's equipment and its limitations is the key to breaking past all that
    so why limit them and paint everyone with the same brush?

    i doubt the ts is like that, same goes for most of the ppl who have been posting here
    Stop being self-centered. I'm not talking about you.

  11. #11

    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by raincool2005 View Post


    sometimes, even a f1.4 lens !
    Bro face the fact la... all camera hunt..except our is extremely bad..
    if all fail..use manual focus
    Last edited by eow; 16th October 2007 at 01:29 AM.
    头可断,血可流,倩女不可不追求 carpe diem,when in doubt, hoot first,apologise later:p GALLERY

  12. #12

    Default Re: what cause lenses to "hunt" during AF ?

    AF works best with lines or some shape. If you have all straight lines, or nothing at all, it's gonna hunt a lot. Find something diagonal, or tilt your camera diagonally for it to lock on, then tilt back - then it will work.

  13. #13
    Senior Member zac08's Avatar
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    Default Re: what cause lenses to "hunt" during AF ?

    Most AF modules are meant to look for a clear difference in light, contrast or pattern.

    If the subject you intend to focus on, does not have a clear difference or has similar patterns all over, then it's hard for the AF module to lock on. Note that sometimes during macro shooting, the lens may also hunt even when the subject has a clear definition and colour. This could be due to the fact that the subject may not be in the AF tracking point during the focusing action.

    [+] [+] [+]

    Let's say it's dead centre already at the red colour, but when you allow the AF function, the lens on moving back and forth, it may have moved such that the subject may be at the left or right of the focusing point and not make the sensor catch on correctly and make the module keep hunting.
    Michael Lim
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    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by raincool2005 View Post


    sometimes, even a f1.4 lens !
    Yah I wonder why too, even on a patterned/contrasty surface with imo adequate light. Am quite disappointed and caused lots of missed or soft shots. Wonder if it is my lens or camera or technique?

  15. #15

    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by raincool2005 View Post


    sometimes, even a f1.4 lens !
    It hunts when there are multiple objects within the same focus area and their distances are different, eg tree branches. The camera won't know which one to lock focus with. Even D2X when put to this kind of situation will hunt.

    Learn to identify objects and features where you can use to lock focus so that next time, you can be confident of yor focus.

  16. #16

    Default Re: what cause lenses to "hunt" during AF ?

    Hope this won't me mis-construed as being unhelpful, but I still prefer a rough ground glass for ultra quick focus, and a split-image for precise focus. AF is a gift of speed and convenience, but not everyone can afford a $6000 or $12000 camera for the best AF. I think the majority bulk of photogs get by (or have to live with) with $1K+ bodies.

  17. #17
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    Default Re: what cause lenses to "hunt" during AF ?

    AF hunts due to the reasons stated zac08,

    just something to add, cameras will also have problem in grey tone(18% if i am not wrong).
    Member of the earth

  18. #18

    Default Re: what cause lenses to "hunt" during AF ?

    but even with a split prism, without contrast, its going to be a bitch to manual focus since both ends of the prism will show the same thing...

  19. #19
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    Default Re: what cause lenses to "hunt" during AF ?

    when the camera AF system cannot find something to lock focus on it will hunt for it.
    firsty understand what the camera needs to lock focus on
    and what it cannot focus on.

    the lens is not the main equipment here
    but it will help the camera, if it was brighter and more contrasty for the camera AF sensor to "see"

    the user manual has this information (illustrated with diagrams)

  20. #20

    Default Re: what cause lenses to "hunt" during AF ?

    Quote Originally Posted by hacknet View Post
    but even with a split prism, without contrast, its going to be a bitch to manual focus since both ends of the prism will show the same thing...
    Well, I guess that's correct, but I don't often take pictures of completely flat white walls or models wearing starched glass-flat fabric, or cloth or other things that are completely lacking in texture, shape, lines or contrast, do you?

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