Is this element misalignment or something else?

Discussion in 'Photography Beginners' Forum' started by purpleroan, Sep 18, 2017.

  1. TCampbell

    TCampbell Been spending a lot of time on here!

    Joined:
    Mar 31, 2012
    Messages:
    3,295
    Likes Received:
    1,415
    Location:
    Dearborn, MI
    Can others edit my Photos:
    Photos OK to edit
    You are attempting to assess the optical quality of the lens using a moving image. Don't do that.

    If the lens has an optical flaw, then that flaw would show up even in a shot where the camera and lens are on a tripod and you're taking a photo of a non-moving flat-field subject (such as a brick wall).

    There can be lots of reasons for a blown shot... others have already mentioned image stabilization (the new Canon EF 70-200mm f/2.8L IS USM II is EXTREMELY good) but there are other questions such as ... was the camera in "one shot" AF vs. "AI Servo" (continuous AF)?

    As I zoom in and read the "Mudcats Alumni" text on his shirt, I see blurring to the left - suggestion horizontal camera movement occurred.

    Note that image stabilization isn't a guarantee that you'll get a keeper... it just improves the odds. Also image stabilization helps for camera movement but doesn't do anything for subject movement (where high shutter speeds help). If IS is enabled and you've been tracking, the IS system tries to stabilize (countering your camera motion) but at some point it reaches the limit of travel and has to reset the lens elements... for that moment in time, you'd have blur as the elements shift back to center.)

    Before you send anything in for evaluation and service... do a simple test with a non-moving camera and non-moving subject to make sure the lens works in those situations. If you get sharp results the optics are fine. You can then experiment with the IS system to make sure it's working (hand held photography of a non-moving subject.)

    Since this was a moving subject, you'd want to make sure you were using continuous focus (AI Servo focus mode) and that the focus point was actually on your subject (you could have a combination of missed focus and motion blur.)


     
  2. purpleroan

    purpleroan TPF Noob!

    Joined:
    Dec 30, 2014
    Messages:
    31
    Likes Received:
    6
    Can others edit my Photos:
    Photos NOT OK to edit
    I'm back everyone! So, after reading all of your replies I decided to try and use the micro adjustment feature on my camera body. I honestly didn't notice much of a difference, and I adjusted it specifically at the long end, which is where I have issues. Perhaps I didn't use a distance such as those I'm shooting at, but in order to test it I would have to have either a giant test sheet or something with equidistant marks, neither of which are practical at the moment for me. I have decided to post another sample to see if I can get any more ideas...again, it is sooc. I realize its a terrible photo in general but I was hoping to catch the issue, which I did. The lens is fine until 100/130mm-ish range, and it seems the effect is more dramatic the farther away the subject is, and the faster they're moving. This photo was shot at 1/800s, f/2.8, iso 125, IS off, at 200mm. It's still possible that it needs to be micro adjusted to a finer and more accurate extent, but I honestly don't see ANY area of sharper focus in the newest example, which leads me to believe that may not be the problem..
     

    Attached Files:

  3. photo1x1.com

    photo1x1.com TPF Supporters Supporting Member

    Joined:
    Sep 14, 2016
    Messages:
    714
    Likes Received:
    219
    Location:
    Austria/Europe
    Can others edit my Photos:
    Photos NOT OK to edit
    I think that is a better example to judge. It looks like this is just a bad lens. I have never owned any of the 70-200 f2.8, but I had the same lens at f4.0 twice from Canon and once from Sony. I never had such blurry images. I did own an EF 50mm 1.4, which had a similar sharpness problem when shot wide open, but this particular lens was known for that issue. The 70-200 f2.8 on the other hand has a pretty good reputation. Any chance you can go to a store and compare your copy to another one?
     
  4. Braineack

    Braineack Been spending a lot of time on here!

    Joined:
    Jun 17, 2013
    Messages:
    11,052
    Likes Received:
    4,277
    Location:
    NoVA
    Can others edit my Photos:
    Photos OK to edit
    you shot at 1/800 and it looks like mush -- unless you had IS on and it's causing the problem, I'd say the lens has a fault.
     
    • Agree Agree x 1
  5. purpleroan

    purpleroan TPF Noob!

    Joined:
    Dec 30, 2014
    Messages:
    31
    Likes Received:
    6
    Can others edit my Photos:
    Photos NOT OK to edit
    Precisely. I bought the lens used from amazon almost two years ago, and I never had any issues with it until the past few months. It's had some bumps and all, but never any serious drops. At this point I'm just curious if anybody has ever seen anything like this so that I can know where to point Canon.
     
  6. birdbonkers84

    birdbonkers84 No longer a newbie, moving up!

    Joined:
    Jan 17, 2017
    Messages:
    808
    Likes Received:
    462
    Location:
    Scotland
    Can others edit my Photos:
    Photos NOT OK to edit
    Do you have your camera set to continuous auto focus while the focal point is over the subject?
     
  7. Braineack

    Braineack Been spending a lot of time on here!

    Joined:
    Jun 17, 2013
    Messages:
    11,052
    Likes Received:
    4,277
    Location:
    NoVA
    Can others edit my Photos:
    Photos OK to edit
    did you even look at the photo?

    this is not a focus point issue.
     
  8. birdbonkers84

    birdbonkers84 No longer a newbie, moving up!

    Joined:
    Jan 17, 2017
    Messages:
    808
    Likes Received:
    462
    Location:
    Scotland
    Can others edit my Photos:
    Photos NOT OK to edit
    Settle down some?

    I asked a simple question, no need to get bent out of shape.
     
  9. Braineack

    Braineack Been spending a lot of time on here!

    Joined:
    Jun 17, 2013
    Messages:
    11,052
    Likes Received:
    4,277
    Location:
    NoVA
    Can others edit my Photos:
    Photos OK to edit


    omg. I'm literally jumping out of my seat going crazy!!!!
     

Share This Page