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EOS R8 won't refocus in Manual mode if I choose a different AF point


Recently got the R8 and have been loving it. However, I am having a really weird issue with the autofocus in manual mode. It definitely isn't a big deal, but it is bugging me more than anything.

I am using the R8 in conjunction with the 400mm F/5.6 lens, primarily for video. In the A+ Auto mode, the camera will automatically focus, and if I go from one focus area to a completely different one to the point where it is just a big blur, the camera will automatically keep trying to focus until eventually it does.

However, this is not the case with the manual mode. If I go from one point to the drastically different one, the camera will just stay unfocused until I hit the Back Button Focus. Also, before anybody suggests it, I have "lens drive when AF impossible" turned on, which is what confuses me.

Any help would be appreciated as I have to use my camera tomorrow. Thanks!


Product Expert
Product Expert

Hi jc86,

Since the camera and lens can track you in auto mode that indicates this is likely related to settings. There are some more settings enable to have the camera actively track you. I see you mentioned you already enabled Lens Drive When AF Impossible, and that should stay on. The camera cannot track correctly with the other settings I'll list if that is not enabled.

To check those settings have the camera in manual mode and press the Menu button. Go to the first page under the AF tab and the settings to check will be listed. The ones to set will vary a little bit depending on if you have the camera set to record movies or if it is set to record photos.

If it is set to record movies have Movie Servo AF set to Enable, set AF Area to Whole Area so the camera is using the full sensor to track you, set Subject to Detect to People, and if you prefer you can also enable Eye Detection. That will set the camera to be looking for a human face, it can use the full sensor area to track you, and the servo setting allows it to actively adjust the focus while you move.

If you have the camera set to record photos go to the first page under the AF tab set AF Operation to Servo, AF Area to Whole Area, Whole Area Tracking Servo AF to On, Subject to Detect People, and if you prefer Eye Detection set to Auto. Then go to the third page under the AF tab and set Preview AF to On. Setting the camera that way allows it to use the full sensor area to track you, it is set to look for a human face, and the Preview AF setting allows the camera to adjust focus even when it is sitting idle.


…;;;the camera will just stay unfocused until I hit the Back Button Focus.

I believe this is your issue.  Setting up BBF gives you control over when the camera focuses and when it does not.  

You must press the control button that you have selected BBF and keep it pressed for the AF system to remain active.  This is similar to half-presssing the shutter and maintaining the half-press to keep the AF system focusing.  

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