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Canon 450D autofocus problems

Started Apr 29, 2016 | Questions thread
PhilPreston3072 Senior Member • Posts: 2,660
AI Servo with Back button focus

I've had great results with AI Servo and Back Button focus on my 450D. I used to always use One Shot focus with half-pressed shutter but there would be quite a few where the focus missed, even for static shots. I was quite surprised to get better results with AI Servo and Back Button focus.

It's really the best of both worlds, and I only use the centre point.

Just keep holding the back button down if you want continuous AI Servo focus.  And you can keep holding it whilst you fire the shutter.

If you want one shot focus, just press the back button for half a second and release.  This works for the Focus-recompose technique.  You can also press the back button several times just to be doubly sure of the focus.

I got good results shooting a soccer match and also my 2 year old daughter who always tries to run away whenever I point the camera at her...GRRRR!

(To set back button focus: Go to Custom Function 10 and select option 1.)

(User Manual Pg158.)

 PhilPreston3072's gear list:PhilPreston3072's gear list
Canon EOS 450D Canon EF-S 18-200mm f/3.5-5.6 IS +1 more
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