New 1.4 tele (Canon) -- Hunting???

DogdotsDogdots Registered Users Posts: 8,795 Major grins
edited December 29, 2010 in Cameras
I just got a new Canon 1.4 extender and I'm using it with my 70-200 2.8 IS lens.

What I'm having a problem with is the hunting that is happening. I can't get it to lock onto a bird sitting on a wire. Find that really perplexing since my 70-200 never hunted like that before.

Is this normal?

If this is in the wrong section .. please move me :D

Thanks!

Comments

  • RichardRichard Administrators, Vanilla Admin Posts: 19,962 moderator
    edited December 28, 2010
    Well, you do lose a full stop, so your f/2.8 becomes an f/4, which makes auto focus less efficient. But if it's happening in good light, then something doesn't sound right. ne_nau.gif
  • craig_dcraig_d Registered Users Posts: 911 Major grins
    edited December 28, 2010
    I have observed AF to be slower using that lens and the Canon 1.4 Extender II, but I haven't had hunting problems.
    http://craigd.smugmug.com

    Got bored with digital and went back to film.
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 28, 2010
    Richard wrote: »
    Well, you do lose a full stop, so your f/2.8 becomes an f/4, which makes auto focus less efficient. But if it's happening in good light, then something doesn't sound right. ne_nau.gif

    Yes it does happen in good light. Sunny day today .. bird on wire and nothing around it but blue sky.

    Think it's defective? I've never had my lens hunt when set to f/4 or any other setting unless I'm shooting at something with lots of stuff in the picture.
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 28, 2010
    craig_d wrote: »
    I have observed AF to be slower using that lens and the Canon 1.4 Extender II, but I haven't had hunting problems.

    No hunting issues with your....hmmmmm.

    Maybe it's just me doing something wrong :cry
  • ThatCanonGuyThatCanonGuy Registered Users Posts: 1,778 Major grins
    edited December 28, 2010
    Are you using the ring of fire? If so, try single point.
    Think it's defective? I've never had my lens hunt when set to f/4 or any other setting unless I'm shooting at something with lots of stuff in the picture.

    No, I don't. It could be, but I don't think so. It's doesn't matter if you've set the aperture to f4, it doesn't actually go to f4 until you take the photo. It stays as wide open as possible to assist with AF. Then when you press the button it narrows to f4. Press the DOF preview button and you'll see what I mean; that button will make it go to whatever aperture you set it on, to show you the actual DOF. But with the TC the max is f4, so that's all that gets through to the camera. See the difference?
  • ziggy53ziggy53 Super Moderators Posts: 24,130 moderator
    edited December 28, 2010
    Which camera body?

    How much of the frame does the bird occupy?

    Have you tried manual focus with AF confirmation?
    ziggy53
    Moderator of the Cameras and Accessories forums
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 28, 2010
    Are you using the ring of fire? If so, try single point.


    No, I don't. It could be, but I don't think so. It's doesn't matter if you've set the aperture to f4, it doesn't actually go to f4 until you take the photo. It stays as wide open as possible to assist with AF. Then when you press the button it narrows to f4. Press the DOF preview button and you'll see what I mean; that button will make it go to whatever aperture you set it on, to show you the actual DOF. But with the TC the max is f4, so that's all that gets through to the camera. See the difference?

    I'm doing single point and I tried the DOF preview button and I didn't see a change. I must of did something wrong. I'll try it outside tomorrow.
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 28, 2010
    ziggy53 wrote: »
    Which camera body?

    How much of the frame does the bird occupy?

    Have you tried manual focus with AF confirmation?

    Camera is the 40d. Bird was probably 25ft. from from me ground wise and then up on a wire from there ... maybe 20ft or so high. Should of been an easy shot. I took a look at the photos where it did focus in on a bird and there was background behind it. Hunted some, but focused in on the body. Did try for a head/eye focus ... head was too small for it to focus in on.

    No I've not tried manual focus yet. I was just practicing with sparrows in the back yard. They're not staying put too long to manually focus in on. Winter .. cold feet .. so they don't stay long in one spot. Will work on that too tomorrow.
  • pathfinderpathfinder Super Moderators Posts: 14,708 moderator
    edited December 28, 2010
    The 40D is a fair body, I like mine too, but its AF is not stellar today, even with an f4 lens.

    Try using several AF points and see if it doesn't do a bit better. You might try cleaning the electrical contacts on the lens and the TC too.

    The TC costs you one stop of light, and your f2.8 lens becomes an f4. Pressing the preview button will do nothing if you lens is set to f2.8, but if you have your lens set to f8, and press the preview button your view will get quite a bit darker as the lens stops the iris down to f8, which admits only 1/8th the light that f2.8 does ( 3 stops less ). Most bodies will AF fine at f4, but not as well as f2.8, and may not AF at f8. ( which is f5.6 + a 1.4 TC )

    If you are using a single AF point, it will have to be directly on a part of the bird or the wire, to find a contrast range to grab for AF. Over bare sky it will just futz around.
    Pathfinder - www.pathfinder.smugmug.com

    Moderator of the Technique Forum and Finishing School on Dgrin
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 28, 2010
    pathfinder wrote: »
    The 40D is a fair body, I like mine too, but its AF is not stellar today, even with an f4 lens.

    Try using several AF points and see if it doesn't do a bit better. You might try cleaning the electrical contacts on the lens and the TC too.

    The TC costs you one stop of light, and your f2.8 lens becomes an f4. Pressing the preview button will do nothing if you lens is set to f2.8, but if you have your lens set to f8, and press the preview button your view will get quite a bit darker as the lens stops the iris down to f8, which admits only 1/8th the light that f2.8 does ( 3 stops less ). Most bodies will AF fine at f4, but not as well as f2.8, and may not AF at f8. ( which is f5.6 + a 1.4 TC )

    If you are using a single AF point, it will have to be directly on a part of the bird or the wire, to find a contrast range to grab for AF. Over bare sky it will just futz around.

    My poor 40d :cry -- I keep telling my hubby I need a 5dMKII :D

    Have to admit my 40d's have never let me down before. Hunting like this was never an issue till the converter went on.

    Just played with my lens with and without the converter. I can see the change when checking the DOF with the converter on and set to 4.5, but at 4.0 there's no change I can see. Suppose that's the norm tho. At least my DOF button works rolleyes1.gif

    I thought I was focusing in on the bird with blue sky behind it, but could of been off. Took some photos of a squirrel off in the distance walking on some branches and they came out ok. Didn't hunt when taking that photo. Then again when I was taking a photo of a bolt head on our swing it hunted for awhile. No consistency really.

    I'll try specific tests tomorrow with it.
  • roletterolette Registered Users Posts: 223 Major grins
    edited December 29, 2010
    Dogdots wrote: »
    My poor 40d :cry -- I keep telling my hubby I need a 5dMKII :D

    There are lots of advantages that a 5DII has over a 40D, but AF isn't really one of them...
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 29, 2010
    rolette wrote: »
    There are lots of advantages that a 5DII has over a 40D, but AF isn't really one of them...

    Burst my bubble rolleyes1.gif

    Really?
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 29, 2010
    Took some photos this morning. Did really good on some objects when set at AF. I was impressed. Then tried to take a photo of a leaf with the background that was tree branches. No go. Then tried it with the background an electrical pole. Worked good.

    Then I tried the manual focus on the same shot. Nope. Wouldn't even lock in a focus. So I gave up.

    Came inside and thought about it. Tried it again on manual focus only shot at tree buds on the branches from my computer room window. Window open of course :D It locked on a focus while in manual focus mode. Not one photo was focused when I took a look at them. Not one :cry

    Not a clue what to do from here. Is this all photographer error?
  • roletterolette Registered Users Posts: 223 Major grins
    edited December 29, 2010
    Dogdots wrote: »
    Burst my bubble rolleyes1.gif

    Really?

    If it helps, I promise not to tell your hubby :D

    Looking at AF from the "is 5DII better than 40D?" angle:

    - All 9 AF points on the 40D are cross-type vs. only the center on 5DII
    + 5DII has 6 invisible AF "assist" points
    - The AF point distribution is bunched up in the middle of a much larger frame vs. a much better spread on the 40D
    = Additional sensitivity on center point with f/2.8 or faster lenses
    ? Possibly slightly faster AF acquisition on 40D center than 5DII, but mixed data here.
    + 5DII has AF micro-adjustment

    Other things that aren't strictly AF, but are in the same arena and closely related:

    - frames rate (3.9 fps vs. 6.5 fps)
    - shutter lag (73ms vs. 59ms)
    - VF blackout (145ms vs. 100ms)
  • roletterolette Registered Users Posts: 223 Major grins
    edited December 29, 2010
    Dogdots wrote: »
    Not a clue what to do from here. Is this all photographer error?

    Pathfinder's suggestion to clean the contacts is a good one. Wouldn't hurt to post a couple of example shots with EXIF data intact.
  • ThatCanonGuyThatCanonGuy Registered Users Posts: 1,778 Major grins
    edited December 29, 2010
    I'm doing single point and I tried the DOF preview button and I didn't see a change. I must of did something wrong. I'll try it outside tomorrow.

    No, you shouldn't see a change. With the converter on, the aperture is ALWAYS on f4 (even if you've set it to f8) to help the AF. Then once you press the shutter it changes to f8 to take the photo (again assuming you have it set on f8). The DOF preview closes to f8 to show you what your depth of field will look like. Hence, "DOF preview."
    Took some photos this morning. Did really good on some objects when set at AF. I was impressed. Then tried to take a photo of a leaf with the background that was tree branches. No go. Then tried it with the background an electrical pole. Worked good.

    Then I tried the manual focus on the same shot. Nope. Wouldn't even lock in a focus. So I gave up.

    Came inside and thought about it. Tried it again on manual focus only shot at tree buds on the branches from my computer room window. Window open of course :D It locked on a focus while in manual focus mode. Not one photo was focused when I took a look at them. Not one :cry

    Not a clue what to do from here. Is this all photographer error?

    If the manual focus AF confirmation is off, then I don't think it's photog error. Honestly, it sounds like front- or back-focus. The 40D doesn't have AF microadjustment, so if I'm right, you'll need Canon to adjust either your lens or your body (or both?).

    Opinions?
  • ThatCanonGuyThatCanonGuy Registered Users Posts: 1,778 Major grins
    edited December 29, 2010
    Burst my bubble rolleyes1.gif

    Really?

    Sarcasm?
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 29, 2010
    Sarcasm?

    Yes :D
  • DogdotsDogdots Registered Users Posts: 8,795 Major grins
    edited December 29, 2010
    Here are some photos. No editing done. All jpegs and cropped to 33%. There were hunting issues on the christmas lights. Not as bad as I thought there might be tho.

    1 -- Took this yesterday. Didn't have a problem focusing in on the squirrel using AF. Grabbed the focus right away even with the squirrel moving.


    1140678832_B8mjt-XL.jpg


    2 -- This morning -- Auto Focus


    1140677117_m86Wt-L.jpg

    3 -- Auto focus

    1140677132_psgky-L.jpg


    4 -- Manual Focus on the furthest leaf to the left -- Can't believe I'm posting this one rolleyes1.gif





    1140677142_MhJoE-L.jpg


    I'm wondering if I do need to send in the tele. It's still within the return time to get a replacement if I want too. Nice to hear it's not 'all me' :D
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