AI Servo Disabling Auto-Focus Points & Bleep On Focusing

[erainn]

Hi, I had some really kind and helpful advice on a focus-related thread I recently posted and wondered if anyone can offer some insight on a related issue I noticed with my camera.

My equipment is: Canon EOS 450d/Sigma DC 17-50 mm 2.8 HSM

Well in an effort o better understand auto-focusing and related settings I discovered that AI Servo is reportedly a good 'all round' setting and can focuses right up to moment the photograph is taken.

So on trying a few shots in that mode I noticed no auto-focus points appear in the viewfinder nor does my camera sound a bleep when object is in focus. Hmmmm

Is this usually the case with AI Servo in Auto-Focus? Am I experiencing some kind of default setting that disables those functions?

Any suggestions most welcome.

Erainn

[Manfred M]

First of all, do yourself (and everyone else) a favour and turn off that blasted "bleep" in your menu settings. Listening to that go off is extremely annoying in most situations. It is one of the first things I do when I get a new camera.

I can't comment on how Canon implements the continuous focus functionality, but on Nikon (at least on my D800) the multiple focus points only show up when I am shooting in single servo mode. In continuous, I get a single focus point showing up on the screen. In most of the modes it is a fixed central point, but in a couple of modes (auto and 3D) it does flit about the screen. I suspect this might also be the case with Canon.

I do virtually all my shooting with single point, continuous servo mode, using back-button focus. I generally use a focus / recompose shooting strategy, although I ran into a situation last week where I perhaps should have used a different continuous servo mode. Something I plan to test the next time I get into a similar shooting situation.

[Loose Canon]

If you look at your manual, starting on page 60 should address what you are asking.

And to put Manfred’s mind at ease that blasted “bleep” does not sound in AI Servo! Nor does the focus indicator light indicate focus lock so he won’t have to listen to that either!

Your autofocus points should be there however and it depends on how you have the selection parameters set as to how it works.