Why is view blurry on T3I in viewfinder?

[amoser3]

I have a Canon T3I.  When I look through the view finder and press the shutter half way to focus, the picture is blurry.  When the picture is taken, however, it comes out crisp.  It happens with different lenses.  I cannot get the view in the view finder to come in clearly.

[cicopo]

Check the manual & look for the instructions on setting the DIOPTER. If you don't have the manual download it from Canon.

[captenergy]

Watch this!  https://www.youtube.com/watch?v=la8-VxHAtAg  Thanks for the info - that was my problem!

[Stephen]

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@amoser3 wrote:

I have a Canon T3I.  When I look through the view finder and press the shutter half way to focus, the picture is blurry.  When the picture is taken, however, it comes out crisp.  It happens with different lenses.  I cannot get the view in the view finder to come in clearly.

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Hi amoser3! @cicopo sounds like he's right in having you check the dioptric adjustment, I just wanted to give you a link to the Instruction Manual! Page 19 shows you where the dioptric adjustment knob is, and page 39 talks about how to adjust the dioptric adjustment. You can download the manual here. And you can download the quick reference guide here. Hope that helps!

[TCampbell]

When you adjust the diopter focus, point the camera at a plain non-distracting subject... a plain white wall works great.  

Don't focus the lens... it's actually better if it's deliberately out of focus.

Look *only* at the focusing points and adjust the diopter until the squares look crisp.

The lens is focusing the image onto the "focus screen" -- this is a bit of frosted "glass" inside the camera which is just above the 45º angle reflex mirror.  The distance that light has to travel to hit the mirror and bounce up to the focus screen is the same distance that it has to travel if it goes straight through to the sensor.  Hence if it looks sharp on the focus screen it'll be sharp on the sensor when the shutter opens.

The viewfinder diopter adjustment can actually compensate for the need for prescription glasses (except for astigmatism -- it doesn't correct for that.)  If you do wear you'll find the adjustment for "with glasses" is very different than the adjustment for "without glasses" on.

If the adjustment of the wheel isn't enough to allow you to make the focus squares tack-sharp, you can buy dioptric accessories which slide onto the viewfinder to change the strength of the adjustment.  See:  http://usa.canon.com/cusa/consumer/products/cameras/slr_cameras/eos_rebel_t3i_18_55mm_is_ii_lens_kit...

[Skirball]

As an aside: I'm a Canon shooter, only because when I was shopping at the store for my first dSLR the Nikon camera I was considering had the diopter adjustment off by a sliver and I didn't know about the knob.  I preferred the feel of the Nikon, but it just looked a bit fuzzier to me, so I went with the Canon.  $15,000 of camera equipment later, here I am, all because of a diopter adjustment.

[TCampbell]

That's an awesome story. In fairness, I didn't know about that adjustment either on my first DSLR. My 35mm film camera never had such an adjustment.