topic Canon EF 24-70 L fails to autofocus at 70mm. in EF & RF Lenses

Canon EF 24-70 L fails to autofocus at 70mm.

00derek — Tue, 16 May 2023 20:03:43 GMT

Canon EF 24-70 L fails to autofocus at 70mm.

5D MkIV body.

Not the same problem as losing focus at different focal lengths, which is well documented here.

With the lens set to AF, lens will focus at all focal lengths until I turn to the maximum magnification...fully counter-clockwise. This is on a tripod without moving the camera relative to the subject. In other words, at 24mm autofocus beeps, but going to the max it will not autofocus, even if I move the body slightly to put different objects in the path of the AF points.

If I turn the zoom ring clockwise, just slightly below 70mm, then autofocus works again. I don't remember this being normal behavior.

I cleaned the lens and camera contacts, but no improvement. In fact it does the same thing on a T3i body.

Any thoughts? I can live with it now that I know the workaround, but is it a defect?

cheers

Re: Canon EF 24-70 L fails to autofocus at 70mm.

deebatman316 — Tue, 16 May 2023 20:57:29 GMT

Which version of the 24-70mm lens do you have version 1 or 2. It sounds like the flex cable in the lens may be starting to fail.

Re: Canon EF 24-70 L fails to autofocus at 70mm.

00derek — Wed, 17 May 2023 14:55:13 GMT

version 1, not v2

Re: Canon EF 24-70 L fails to autofocus at 70mm.

deebatman316 — Wed, 17 May 2023 23:10:56 GMT

The flex cable is on the way out. V1 of the lens had this problem.

Re: Canon EF 24-70 L fails to autofocus at 70mm.

00derek — Thu, 18 May 2023 13:24:12 GMT

Thanks!

Is it repairable if I send it to Canon - do they still do repairs?

Re: Canon EF 24-70 L fails to autofocus at 70mm.

deebatman316 — Thu, 18 May 2023 13:52:35 GMT

No not anymore. You can send it to a 3rd Party for repair. Or look into replacement if the repair costs exceed the value of the lens.

Re: Canon EF 24-70 L fails to autofocus at 70mm.

wq9nsc — Thu, 18 May 2023 13:53:54 GMT

You would have to check with Canon to see if version 1 is still repairable, if not a third party shop could likely do so.

With the zoom ring set at 70mm, does manual focusing result in proper focus? Hopefully the issue is electrical and not mechanical.

I am still using the 24-70 I bought back in 2005. I have thought several times about grabbing the newer version but I am a bit concerned given the reported failures with it given that my current 24-70 has been perfectly reliable.

Rodger

Re: Canon EF 24-70 L fails to autofocus at 70mm.

00derek — Thu, 18 May 2023 14:04:48 GMT

yes, manual focusing works fine

Re: Canon EF 24-70 L fails to autofocus at 70mm.

shadowsports — Thu, 18 May 2023 15:00:51 GMT

Greetings,

Not sure if the v1 is still under repair support. Register in your My Canon account to see support options. If its not, you can contact midwestcamera dot com. They are a authorized Canon repair agent and should be able to do this for you fast and reasonably.

Re: Canon EF 24-70 L fails to autofocus at 70mm.

HDDENB — Thu, 02 May 2024 22:48:40 GMT

How does one know if the lens is v1 or v2. This focusing issue appears to be happening to my 24-70L (on a markiv5d) again. This happened while in France 2 years ago. I had it repaired, and now appears to be happening again now while in Portugal …:(

Re: Canon EF 24-70 L fails to autofocus at 70mm.

ebiggs1 — Fri, 03 May 2024 13:38:10 GMT

" If its not, you can contact midwestcamera dot com."

They went out of business at the first of the year. Try phototronic.biz instead.

Re: Canon EF 24-70 L fails to autofocus at 70mm.

ebiggs1 — Fri, 03 May 2024 13:43:38 GMT

"How does one know if the lens is v1 or v2."

There is no v1 or v2. These are names, words, people come up with to try and distinguish between the models but can be confusing since they are not accurate. There is a Mk II (no Mk I) and its full name is Canon EF 24-70mm f/2.8L II USM Lens. The first model doesn't have the "II" in its name. The Canon EF 24-70mm f/2.8L USM Lens.