Autofocus Sttoped Working

[autoclinic]

Hi
I need help with my Canon Xti or 400D as autofocus sttoped workig while pressing sutter relese butten it try to focus but the lens keep moving and can't take a snap but when I use manual focus it is working fine . Please help if there is faulty internal battery or a different problem or just to reseset the camera setting
Thasnks
Waseem

[Frog]

I don't know but are you trying to focus on something that is closer than your lenses minimal focal distance?
Does it happen all the time or with certain lenses or situations?

[autoclinic]

I don't know but are you trying to focus on something that is closer than your lenses minimal focal distance?
Does it happen all the time or with certain lenses or situations?

Yes it does with both my lenses and it is not the distance problem I am sure there something different wron with my camera

1. Canon .EF -55mm
2. Tamron Af 55-200

[.tony. .riot.]

My Sigma 70-300mm won't autofocus.

[autoclinic]

Do you think if it could be weak internal battery of the camera there is one not allowing to autofocus.

[autoclinic]

sorry if there is one internal battery in the camera not allowing to autofocus

[.tony. .riot.]

In your case it happens in both lenses, for me it's only with the Sigma. So I'm pretty sure my case is the AF motor on the lens, not the camera.

[autoclinic]

In my case it's the camera surely not the lenses because both lenses were working fine last time when I took about 50 photos with both lenses.
Have you tried any other autofocus lens on your camera?

[.tony. .riot.]

Yup. Just tried my 12-24mm and it works fine.

time for a new 70-300.

[OldClicker]

We really need more information. There are many reasons for AF problems. Does it work in bright light? Does it fail at all distances? Which of the AF types is it set at (One Shot, AI Focus, AI Servo)? Does it only fail when trying to focus on certain things? When did it start/what is different? - TF

[freygr]

Just remember some lenses have a Manual/Auto Focus Switch on the lens! Check the lens again and the contacts on the lens.

[byjamesderuvoDHQ]

You may be in AI Focus Servo Mode. As such, it's focusing rather like a camcorder. Reset your camera back to single shot and you shoudl be good to go.