topic Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM in EF & RF Lenses

Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Wandalynn — Wed, 13 Sep 2023 01:32:20 GMT

I had seen in another post about a firmware update for the EF 100-400mm f/4.5-5.6L IS II USM (which I discovered the previous 1.0.6 version on mine). I hope this isn't a dumb question but can I do the update via an RF to EF adapter on my R5 or R6ii?

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Anonymous — Wed, 13 Sep 2023 01:58:23 GMT

I would think that if it is a Canon adaptor, you should be good to go. If you did the download of the firmware update file, it has instructions included.

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

shadowsports — Wed, 13 Sep 2023 03:56:37 GMT

Greetings,

I agree with Bob. If the current FW for the lens displays in the R5's menus, you should be able to apply the upgrade. Please put the "EF008107.lfu" file on the root of a freshly formatted (in camera) SD card. If you have a CF Express card installed, remove it temporarily prior to performing the upgrade. You will also want to use a fully charged battery.

While the behavior that v1.0.7 addresses is rare, I'd install it to be safe.

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Wandalynn — Wed, 13 Sep 2023 13:09:21 GMT

Thank you to both people who replied--am glad to hear that. The fix Canon described for the image sometimes "jumping around" is a situation I have sometimes experienced with that lens so I am interested in the update. I keep my camera firmware up-to-date but forget to periodically check on lens updates. Wanda

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

shadowsports — Wed, 13 Sep 2023 13:17:13 GMT

I'm behind with two of my lenses right now as well. I think the updates add focus breathing correction which I don't even have on my body but I'm sure my next one will 😀

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Anonymous — Wed, 13 Sep 2023 14:38:50 GMT

Version 1.0.7 is supposed to address an IS problem with the lens. Hope it cures your problem. It sounds like your issue is related to image stabilization in the lens.

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Wandalynn — Wed, 13 Sep 2023 18:10:07 GMT

I hope so--I don't see that happen with my other lenses, and, luckily, only rarely with the EF 100-400. Thanks!

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Anonymous — Wed, 13 Sep 2023 18:16:03 GMT

Let us know if the firmware solves the issue.

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Wandalynn — Sun, 17 Sep 2023 19:10:00 GMT

I updated the firmware a few days ago and have spent a little time testing out the lens. So far so good. Even though the problem occurred only rarely, I feel as if the update will continue to serve me well. Thanks for your input and help!

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

Anonymous — Sun, 17 Sep 2023 19:14:56 GMT

Good news.

Re: Question about Firmware Update to EF 100-400mm f/4.5-5.6L IS II USM

shadowsports — Sun, 17 Sep 2023 19:57:51 GMT

Excellent. I did 3 lenses last night and actually reviewed the update procedure. It does change depending on your hardware. I noted this. ➡️ OK to use supported mirrorless body to upgrade EF glass with EF to R adapter.