Canon EOS 20D Autofocus - Serious Problem?

Discussion in 'Canon' started by Jim Garrison, Nov 14, 2005.

  1. Jim Garrison

    Jim Garrison Guest

    I spent ~$2000 on an EOS 20D and 17-85 IS USM lens in June of this
    year. So far it's been back to the factory for repair twice.

    The first time was for flash exposure problems, which were fixed,
    and severe back-focus, which was not fixed. I sent it back in and
    it came back with the same problem. Canon's stock answer is "send
    it in for repair". Well, I've done that twice without the problem
    being corrected.

    I've read in various forums that this particular lens is somewhat
    'soft', but my experiments show that I can get more sharpness
    focusing manually than the camera will produce on autofocus.
    Yes, the lens is a little soft, but not as soft as you might
    think from autofocus shots, at least on my camera.

    I've posted test samples at http://www.jhmg.net/misc/canon/ that
    were made using a focusing test chart. The central focus point was
    selected and placed on the black bar in the middle of the image, so
    that the top edge of the black bar ran through the middle of the
    focus point. The camera was on a sturdy tripod, the angle
    between the plane of the chart and the camera lens axis was 45
    degrees and the camera distance was about 36". A cable release was
    used to eliminate the possibility of camera shake.

    I'd like to hear from others that have the same problem, or
    conversely, if this kind of performance is the best the technology
    can do today I need to know also, even though that would be
    disappointing.

    If the consensus is that the lens is defective, does anyone know how
    to get past Canon's first-level support drones and escalate this to
    someone who can do something about it?
     
    Jim Garrison, Nov 14, 2005
    #1
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  2. Jim Garrison

    UC Guest

    No sympathy from me. Buy a Leica and use film, moron
    Ha ha ha ha ha ha ha ha ha ha ha ha

    Autofocus? Who needs ithat?
    No shit, Sherlock.

    Japanese zoom crap.
    No, I don't have the same problem. I use a 30-year old Leicaflex that
    continues to work perfectly year after year. I'm not a moron like you
    who is too fucking lazy to focus, and too fucking stupid to buy good
    equipment (not Jap crap.)
    Technology is not the answer, fuckhead, quality is.
    Ha ha ha ha ha ha ha ha

    Dumbass motherfucking moron shithead dweeb consumer asshole...
     
    UC, Nov 14, 2005
    #2
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  3. Jim Garrison

    UC Guest

    Do you have to hire someone to keep you breathing? Are you really so
    fucking stupid that you believe all this digital-autofocus-zoom lens
    crap?

    People like you deserve all the shit that life throws at you. I have no
    sympathy for utter morons like you. I hope every camera you buy uis a
    piece of crap, that your lenses are shit, because that's what cheap
    assholes like you deserve.

    Complain all you want, Mr Garrison...the problem is YOU and your
    stupidity...
     
    UC, Nov 14, 2005
    #3
  4. Ignore the trolls.

    I have one and I have not had any problems with it. The lens seems to
    auto-focus just fine.
     
    Joseph Meehan, Nov 14, 2005
    #4
  5. Jim Garrison

    Backbone Guest

    Do you have to hire someone to keep you breathing? Are you really so
    PLONK!!!
     
    Backbone, Nov 14, 2005
    #5
  6. Jim Garrison

    Skip M Guest

    He changed his nic so as to escape the kill files of all the people who are
    sick of his monomaniacal rantings. He's an idiot who has never taken a
    decent image in his life, even given the best of equipment. Or at least he
    claims to have the best of equipment.
     
    Skip M, Nov 14, 2005
    #6
  7. Jim Garrison

    Herb Ludwig Guest


    AFAIK the EOS20D has an autofocus that functions differently with lenses
    above 2.8 max aperture and stops more or less functioning with lenses max
    5.6 or above.
     
    Herb Ludwig, Nov 14, 2005
    #7
  8. Try turning off all the other autofocus points except the one in the
    middle. I had the same problem. Sometimes the center autofocus spot would
    be on what I wanted, but one of the other ones would be on something a
    little further. Using only the center spot gives me perfect
    autofocus...well at least better than I can do with my eyes.
     
    William Oertell, Nov 14, 2005
    #8
  9. Jim Garrison

    Stacey Guest

    He said he has already done this, see above.


    I had a problem with a canon printer and had to get pretty nasty with the
    people on the phone, told them I had e-mailed and called MULTIPLE times and
    got the same responce from people who didn't understand the products (Kept
    telling me to defrag my hard drive for a printer color shift problem?)
    Finally it got sent to someone with a brain who understood the problem, who
    OK'd replacing the printer and gave me an RMA. the replacement printwer
    works great. I'd call again, tell them you've had it in for service twice
    for the same problem and you are tired of this run around and need to talk
    to "the next level" of support. It's hard to say if it's the lens or the
    camera that's the problem but seems to be an issue with canon's autofocus
    system on certain samples?
     
    Stacey, Nov 14, 2005
    #9
  10. Jim Garrison

    Dirty Harry Guest

    http://redwing.hutman.net/~mreed/warriorshtm/troller.htm
     
    Dirty Harry, Nov 14, 2005
    #10
  11. Not sure on your laws, but we have one that says the unit must be capable of
    performing the task it was designed to do - and clearly a camera that takes
    out of focus images fails - putting the onus on the manufacturer to take
    reasonable steps to put it right - if they don't (or can't) then you're
    entitled to a refund or replacement.

    Perhaps you have a similar law that you could use as leverage.

    I'd be surprised if they test cameras or lenses in any subjective way at
    all - I would imagine that they hook it up to some kind of computerised
    optical testing equipment, which gives it a pass or a fail - it seems to me
    that they think the camera/lens is performing OK (ie a 'fault not found") -
    which means there isn't anything wrong, or what you're seeing isn't being
    picked up by the tests. Are you able to test the camera with any lenses that
    are considered to be "above reproach" (24-70 F2.8L USM or 70-200 F2.8L USM?
     
    Cockpit Colin, Nov 14, 2005
    #11
  12. It's probably not the lens which is defective. Tolerance in all DSLRs
    are pretty poor, and in the UK most national news agency Canons,
    including the most expensive, are calibrated by Fixation, an independent
    repair firm which positions the sensor, AF assembly and checks
    collimation of mirror and focusing screen. They do the same for Nikons
    ex-factory too. They have sensor cleaning contracts with newspaper and
    agency depts, and also correct for the common back, front and skew focus
    errors found in DSLRs of all price categories.

    Since the makers will not admit that there is a general difficulty
    making sure any CCD/CMOS assembly actually falls plane parallel and axis
    centered at true infinity focus and collimated with the mirror/focusing
    screen assembly AND the AF module, it's pretty hard to get any of the
    warranty depts to commit themselves to a proper adjustment on a DSLR body.

    It is hardly ever the lens which is the *cause* of the problem; specific
    lenses may REVEAL the problem, and that tends to mean very short lenses
    (10-20mm) and/or wide apertures (f2.8+). You will see the problem on a
    50mm f1.4 or an 85mm 1.8 as well as on a 17mm f2.8, but you may not see
    it at all on an 18-55mm f3.5-5.6. Add to this specific issues such as
    mutiple AF point selection and spurious contrast detection (under which
    a lens can appear to snap into focus when it's not in focus at all, the
    sensor is merely detecting a phase effect in the unfocused image) - plus
    the difficulty of manual focusing with the near-transparent focus screen
    used to keep smaller DSLR finders acceptably bright to the eye - and you
    have a situation where the average semi-pro/pro AF DSLR is slightly less
    useful for reliable sharp focus than a 1960s Pentax Spotmatic with a
    microprism aid.

    David
    f2photo.co.uk
     
    David Kilpatrick, Nov 14, 2005
    #12
  13. Jim Garrison

    Donald Gray Guest

    On 13 Nov 2005 16:55:14 -0800, "UC" <>
    wrote:

    [garbage cut]

    You are the weakest link - goodbye.

    Kerrrrrr Plonk! into teh killfile you go....
     
    Donald Gray, Nov 14, 2005
    #13
  14. Jim Garrison

    fab Guest

    David Kilpatrick ha scritto:
    does the fixation have a web site or an email address?
    thanks
    fabricius
     
    fab, Nov 14, 2005
    #14

  15. Could this be the place?

    http://fixationuk.com/news.htm
     
    Philip Bailey, Nov 14, 2005
    #15
  16. Jim Garrison

    UC Guest

    the poster is stupid, cheap, and lazy. He's another typical moron
    American zombie with no wits.
     
    UC, Nov 14, 2005
    #16
  17. Jim Garrison

    UC Guest

    Is this how you want to live your life? Waiting on the phone with
    'support' people? To coin a phrase: "**** that shit"! Give me da film,
    man!

    You morons can keep your stupid digital shit, I want no part of it...
     
    UC, Nov 14, 2005
    #17
  18. Jim Garrison

    UC Guest

    David Kilpatrick wrote:
    Add to this specific issues such as
    Ha ha ha ha.

    In 35 years, no real progress at all......!

    My 1974 Leicaflex SL2 out-performs all of those digital autofocus
    pieces of shit....

    Can you say 'there's a sucker born every minute' in Japanese?
     
    UC, Nov 14, 2005
    #18


  19. www.fixationuk.com


    They also have a camera shop

    David
     
    David Kilpatrick, Nov 14, 2005
    #19
  20. Jim Garrison

    Skip M Guest

    Hook, line and sinker. Great retort, bub.
    And top posted to boot...
     
    Skip M, Nov 14, 2005
    #20
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