09-02-2022 08:54 PM
Hey y'all,
I recently purchased the 70-200mm lens and am trying to use it on my canon 5d mark iii. The lens won't autofocus no matter what settings change or no matter which firmware I use. I'm currently on firmware 1.3.6. I have also ensured that the lens is set to auto not manual. Is there anything that I am missing to be able to use this lens? the autofocus works on my M50 with an adapter, but not on my 5D.
Solved! Go to Solution.
09-03-2022 06:28 PM
This is strictly a lens issue then. Sigma or a 3rd party will need to repair the lens.
-Demetrius
40D, 5D IV, EF 16-35mm F/2.8L III, EF 24-70mm F/2.8L II, EF 28-135mm, EF 50 F/1.8 STM
430EX III-RT, 600EX II-RT
09-04-2022 11:14 AM
It needs to go back to Sigma for service.
I don't have every "old" Sigma lens made but the ones I do have, a substantial number, all have worked. I have run across a few older Tamron and Tokina lenses that have problems. Matter of fact I have the EX 70-200mm f2.8 which works fine.
09-03-2022 01:04 PM
That is the lens I am trying to use. I can’t find any forum posts or similar issues with the same body and lens. I am assuming it’s an issue with the lens. It functions on my m50 kinda. The camera doesn’t have an issue with any other lens. I have cleaned the contacts on the lens and the camera and it didn’t make a difference
09-03-2022 03:56 PM
Cleaning contacts rarely fixes anything, not unless you can see visible debris or discoloration. The mere act of mounting and dismounting the lens creates sufficient friction on the contacts to keep them clean.
Make sure the camera body contacts are springy and not getting stuck. Otherwise, I do not know what else to do about it. They just do not want to play together.
09-03-2022 02:34 PM
What do you mean by it works on your other camera kinda. Is it slow to AF or have any other issues.
-Demetrius
40D, 5D IV, EF 16-35mm F/2.8L III, EF 24-70mm F/2.8L II, EF 28-135mm, EF 50 F/1.8 STM
430EX III-RT, 600EX II-RT
09-03-2022 03:30 PM
On the m50, it is constantly focusing even when not engaging back button focusing. Holding down the focus button doesn’t make any changes
09-03-2022 03:57 PM
Mirrorless cameras work a little differently compared to a DSLR.
09-03-2022 05:27 PM
Does OP have BBF (Back Button Focus) setup on their 5D III. Since the shutter and AF Start buttons have been decoupled now.
-Demetrius
40D, 5D IV, EF 16-35mm F/2.8L III, EF 24-70mm F/2.8L II, EF 28-135mm, EF 50 F/1.8 STM
430EX III-RT, 600EX II-RT
09-03-2022 05:46 PM
Yes I do. I put the camera to factory settings and it didn’t help. I also tried to have a few different buttons operate the AF and it didn’t change anything
09-03-2022 05:50 PM
A factory reset does not always clear (CF) custom functions. Try the camera in A+ Mode (Full Auto) overrides all custom functions.
-Demetrius
40D, 5D IV, EF 16-35mm F/2.8L III, EF 24-70mm F/2.8L II, EF 28-135mm, EF 50 F/1.8 STM
430EX III-RT, 600EX II-RT
09-03-2022 06:02 PM
No luck with that either. I have chalked it up to a failure of communication with the lens and body
09-03-2022 06:06 PM
Usually a faulty communication will cause an error code of some kind. It also seems strange that it works when its adapted to an EOS-M/ EF-M series body.
09/26/2024: New firmware updates are available.
EOS R5 Mark II - Version 1.0.1
EOS R6 Mark II - Version 1.5.0
07/01/2024: New firmware updates are available.
04/16/2024: New firmware updates are available.
RF100-300mm F2.8 L IS USM - Version 1.0.6
RF400mm F2.8 L IS USM - Version 1.0.6
RF600mm F4 L IS USM - Version 1.0.6
RF800mm F5.6 L IS USM - Version 1.0.4
RF1200mm F8 L IS USM - Version 1.0.4
Canon U.S.A Inc. All Rights Reserved. Reproduction in whole or part without permission is prohibited.