Rebel t3i viewfinder is blurry, not the diopter adjustment.

[sb5]

Ok, I own a Rebel t3i. Everytime I look in the viewfinder, it's blurry. However the picture comes out crisp. It isn't the diopter adjusment. Sometimes when I hold the camera up and wiggle it, the viewfinder will be clear for a couple seconds, then it'll go back to being blurry. There aren't any camera shops around me, and I'm in to sports photography and it gets very frustrating having to look at the blurry viewfinder. Hope somebody can help!! Thanks. 🙂 

[TCampbell]

Remove your lens and look at (but do not touch) the focus screen.  The focus screen is located above the reflex mirror.

The camera is projecting an image onto that screen.  The distance from the back of the lens to the reflex mirror and up to the screen is the same as the distance straight through the to the imaging sensor at the back of the camera.  So if the focus screen is in place, an image focused on the screen will appear the same way on the sensor when you take the shot.

I'm wondering if something has dislodged your focus screen.  It should be snugly in place.  You might give your camera a gentle shake when looking inside and see if it moves. 

There's a frame that holds the focus screen in place and it's possible it came unhunged.  If it did come unhunged, you should avoid touching it as it's easy to smudge it and very hard to clean.  Companies that sell replacement screens usually include special tweezers so you can swap screens without actually touching it.

[cale_kat]

sb5, you say it isn't the diopter adjustment but why? Is it because the image in the viewfinder can not be adjusted for focus using the diopter? If that's the case, maybe the diopter is broken.

If you think it isn't the diopter because sometimes the viewfinder is clear but othertimes it isn't then I think Tim might be on to something. Of couse, an event that would knock the focus screen loose would usually be memorable. (Say the camera took a dive.) Generally speaking, critical parts of a camera are not knocked loose in any casual sense of the word.

Do you, by chance, shoot while wearing glasses? If so, and assuming the camera isn't broken, there are accessory eyepieces that might improve your sports photography.

Good luck.

[ebiggs1]

First you need to reset the camera to factory defaults.  Remove all bateries for a while ( a few hours).  When something is going awry that is the first thing to try.

Next try a different lens.

I doubt the focus screen is loose but the mirror may not have come back to it's normanl position.  No one 'accidently' stuck a finger inside the mirror box?  Maybe while cleaning?

Lacking any successful, I think you have a trip to Canon service in your future.

[iuaassoc]

Did you find a fix for this. My Rebel XS has exactly the same issue which was caused by a good hard drop from 5 feet. I can hear something "flop" when tipping the camera slightly up which causes the diopter to be focused.

[RobertTheFat]

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@iuaassoc wrote:
Did you find a fix for this. My Rebel XS has exactly the same issue which was caused by a good hard drop from 5 feet. I can hear something "flop" when tipping the camera slightly up which causes the diopter to be focused.

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A "good hard drop from 5 feet" is going to seriously damage an SLR almost every time. In the case of an old Rebel, it has to be regarded as fatal, because the repair shop is likely to charge you more to fix it than the camera's replacement cost.

I have no idea what you mean by "causes the diopter to be focused". (A "diopter" isn't an object; it's a unit of measure of the strength of an eyepiece adjustment.) But it doesn't matter; your camera's goose is probably cooked in any case.

[iuaassoc]

Well the camera's goose is not really cooked - it still takes perfect pictures - even with the viewfinder being out of focus. For clarity - the viewfinder (my mistake I guess refering to that as the diopter) will become properly focused when the camera is tipped slightly upwards and revert to out of focus when returned to level. I agree that the cost to repair at a shop will likely be prohibitive - the exact reason for my seeking the assistance of knowledgable forum contributors.

Thanks

[iuaassoc]

I should mention that the camera takes perfectly focused pictures and the focus plate is in place.  The issue is definitely within the viewfinder, you can hear a "flap" of siome loose component when tilting the camera up.  I also took the focus plate out and you can see into the viewfinder area that there is a loose piece of glass between the external eyepiece glass and the glass of the viewfinder closest to the mirror.

I can continue to use the camera using auto focus but it is impossible to manually focus with this issue.

[ebiggs1]

"good hard drop from 5 feet"

Unless it is a 1 series, this is a death sentence for most cameras.  Depending on what it is dropped on to.  Concrete? 

But the diopter adjustment?  And everything else is good to go?  Seems like an unusual circumstance.  Usually the lens and mount break off.

[iuaassoc]

Dropped on concrete but still taking great pictures - it is only the viewfinder focus that is failing. In fact, I can position the camera slightly upwards and to the left and rap it so that the viewfinder lens somehow stays in place for a couple pictures when returned to level. The viewfinder lens must have become detached from the adjustment knob. If too expensive I will just live with it but I would much rather return it to its previous condition.