T3i Blurry Photos all of a sudden

[liamket]

I have a Rebel T3i and have really enjoyed using it over the years.

recently, and all of a sudden, it has started having trouble focusing.  Some low light situations, or indoor shots, the camera really struggles to find its focus and oftentimes, won't even take the picture.

Outdoors isn't as bad, but the photos are all just slightly out of focus, even if I carefully, manually focus... The pictures just come out looking like crap.

I've tried 4 different lenses (both fixed and telescoping), and have the same issue with all of them.

I've cleaned the terminals, reset the camera, reinstalled firmware, etc.

I've always been pretty careful when changing lenses, and the mirror/interior looks really clean...

Any ideas would be appreciated.

[kvbarkley]

There could be dirt/grunge on the AF sensor below the mirror. Does it focus in live view?

[liamket]

i believe so.

I've turned on the screen in the back, used the magnifier to zoom in on the picture, and manually focused the lense to where it looks good.  Take the picture, go back into review and zoom in on it, and it's not crisp.

[kvbarkley]

You might be being too hard on the camera. No image, even when perfectly focused, will look sharp at magnified view on the camera.

That said, are you magnifying what the camera is focused on?

Are you focusing on a flat wall or test pattern at f/8 or so so that it should all be in focus?

[liamket]

i will do some of those tests when I have a chance.

The things I mentioned above were simply things I tried to do to help potentially troubleshoot the problem.  I recognize that a manual focus under magnification isn't going to be perfect.  But my thought process was that if there is still an issue, even when manually focusing to the best of my ability, then it might rule out an auto-focus issue.

I also understand that settings and technique play a big role in whether you will get clear photos.  However, there was a very distinct change in the camera's ability to function.  I consider myself a somewhat capable amateur photographer.  I can't for the life of me get more than 1 out of 20 photos in focus at this point and the one good one is probably a fluke.

What's the difference between cleaning the mirror/sensor and the AF sensor you mentioned is behind it?

[kvbarkley]

The AF sensor controls Autofocus, so might be your problem. It is at the bottom of the mirror box so that light comes in and most reflects 45 degrees *up* to the viewfinder and a fraction goes 45 degrees *down* to the AF sensor.

But, if you don't get adequate focus in live view which does not use the AF sensor, that is not the problem.

[Waddizzle]

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@liamket wrote:

i will do some of those tests when I have a chance.

What's the difference between cleaning the mirror/sensor and the AF sensor you mentioned is behind it?

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If I were you, I would not touch anything inside of the camera body.  Do not attempt to clean it by wiping it off.

[BurnUnit]

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@liamket wrote:

I've turned on the screen in the back, used the magnifier to zoom in on the picture, and manually focused the lense to where it looks good.  Take the picture, go back into review and zoom in on it, and it's not crisp.

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Do the images look blurry on your monitor when viewed at 100% magnification?

[ebiggs1]

"I would not touch anything inside of the camera body.  Do not attempt to clean it by wiping it off."

"I would not touch anything inside of the camera body.  Do not attempt to clean it by wiping it off."

"I would not touch anything inside of the camera body.  Do not attempt to clean it by wiping it off."

Nothing smaller than a football do you stick in there!