Strange focus issues

racerracer Registered Users Posts: 333 Major grins
edited February 2, 2011 in Cameras
I am using a Canon 50d as my main camera, but I also sometimes use my old Rebel XTi as a second camera so I don't have to change lenses.
The other day I took a bunch of shots with the Rebel and realized that something is wrong with it. Every shot I took with it, the left third of the image is horribly out of focus, while the rest of the image is acceptably in focus. The photos look horrible, to the point I am going to have to scrap them. I tried different lenses, and tried the same lenses on the 50d, the lenses are fine, so it must be something with the camera.

I have had this camera since 2007, lost track of the photo count a long time ago, and have never cleaned the sensor :eek1. Is there maybe just to much dirt inside of it? I might have just abused it one to many times :cry
Todd - My Photos

Comments

  • QarikQarik Registered Users Posts: 4,959 Major grins
    edited January 31, 2011
    can we see a shot?
    D700, D600
    14-24 24-70 70-200mm (vr2)
    85 and 50 1.4
    45 PC and sb910 x2
    http://www.danielkimphotography.com
  • Matthew SavilleMatthew Saville Registered Users, Retired Mod Posts: 3,352 Major grins
    edited February 1, 2011
    You may want to check the sensor for a smear of something, to do that either just take a "bulb" picture with the lens off Laughing.gif, or use the actual mirror cleaning menu option to open the shutter WITHOUT making a white exposure...

    It could also be the mirror or shutter that is causing a weird blur, however if you're saying the issue us left and right as opposed to up and down, I doubt it's either the mirror or the shutter.

    It's also likely that it could indeed be a lens issue. I guess the camera could be either going haywire with focus every few images, and it just so happens to focus on something on the left by accident, ...but the more likely issue is that the lens has an element out of alignment or something. But again, I'm tempted to doubt that possibility as well because you tried the same lenses on the 50D.

    Post a high-res image of a brick wall lol, and we might be able to tell you if it's an issue with a mirror, shutter, lens, or sensor, etc...

    =Matt=
    My first thought is always of light.” – Galen Rowell
    My SmugMug PortfolioMy Astro-Landscape Photo BlogDgrin Weddings Forum
  • racerracer Registered Users Posts: 333 Major grins
    edited February 2, 2011
    Could this be a issue with using the camera in the cold, not fogged up, but low temperatures affecting it?
    I took some photos inside and all was good, but using it outside in the cold again resulted in horrible results again.
    Never had a problem in the cold before, and have previously taken thousands of photos with it in cold tempeture with no problem ne_nau.gif
    Todd - My Photos
  • ziggy53ziggy53 Super Moderators Posts: 24,130 moderator
    edited February 2, 2011
    May we see some examples of the problem?
    ziggy53
    Moderator of the Cameras and Accessories forums
  • racerracer Registered Users Posts: 333 Major grins
    edited February 2, 2011
    ziggy53 wrote: »
    May we see some examples of the problem?
    I was hoping to avoid showing the pictures :hide , they are really bad, and it all cant be blamed on the camera rolleyes1.gif

    I think I have come to the conclusion that it has something to do with using it in the cold.
    Can cold temps affect a camera other then fogging? Does the battery getting cold have a effect on the working of the camera, or does it only lower the number of photos you can take per battery?
    Todd - My Photos
  • ziggy53ziggy53 Super Moderators Posts: 24,130 moderator
    edited February 2, 2011
    We are not in this thread to judge your photography. We are trying to help. It's hard to help without seeing the problems, since it could be a number of different or even combined issues.
    ziggy53
    Moderator of the Cameras and Accessories forums
  • racerracer Registered Users Posts: 333 Major grins
    edited February 2, 2011
    ziggy53 wrote: »
    We are not in this thread to judge your photography. We are trying to help. It's hard to help without seeing the problems, since it could be a number of different or even combined issues.

    Yes, I got that, but I asked if a camera could be affected by the cold and causes this type of problem, if it can, then this would confirm that this was indeed the issue I was having.
    Todd - My Photos
  • ziggy53ziggy53 Super Moderators Posts: 24,130 moderator
    edited February 2, 2011
    racer wrote: »
    Yes, I got that, but I asked if a camera could be affected by the cold and causes this type of problem, if it can, then this would confirm that this was indeed the issue I was having.

    Potential problems with cold weather can include:
    • Bringing a cold camera back into a warm and humid environment.
    • Changing a lens on a cold camera inside a warm and humid environment.

    Just taking a camera into the cold generally does not cause issues in the cold environment (with the exception of extreme cold, like below zero F.). Indeed you mentioned that you had done this before with no ill effects. You also mentioned that you tested another body with the same lenses. If you used the same procedure with both bodies and only had issues with one of the bodies that would seem to isolate the problem to just that body.

    I suppose that it's possible for the imager to be flexing in its mount inside the camera. Modern dSLRs use a metal frame to hold the imager and if the metal contracts it could be putting unusual pressures on the imager assembly, causing the imager to "bow". I've never heard of this happening however. Since you used the camera in the cold before I have a tough time accepting that scenario.

    People have been known to inadvertently have part of a gloved hand over part of the lens. When you use gloves/mittens you are less likely to know exactly where your fingers and the glove/mitten is with regard to the lens. I've actually seen people do this and it really can cause a softness to part of the image that is being partially obscured.

    There are more potential things to consider but most things really could be ruled out if we could see the visual nature of the problem. mwink.gif
    ziggy53
    Moderator of the Cameras and Accessories forums
Sign In or Register to comment.