5D4 - can't use live view focus when configured for back button focus

[strutzj]

I use the shutter button to meter only and the AF-ON button to focus in servo mode. However, my live view focus doesn't work. There are references to this issue in this forum and elsewhere but nobody seems to give an explanation or work-around. I can do both (back button focus and live view focus) with my 90D and SL3, surely the 5D4 should also be able to do it. 

[Tim]

Hello strutzj, 

We're sorry this occurs.  Would you be able to let the community know which lens or lenses you are using at the time?  

[strutzj]

Back button focus and live view focus is mutually exclusive on my Canon 5D Mark 4 with any lens I've tried (i.e.: Sigma 24-70mm Art, Canon 24-105mm L, and others). Camera firmware version is 1.2.1. It doesn't matter that the AF-ON button is set to focus, but rather setting the shutter button to meter only is what causes the problem. I shouldn't have to reprogram the shutter button every time I want to switch between back button focus or live view focus. Thanks for any help.

[Tim]

strutzj, 

We're sorry this occurs.  Unusual that it would happen.  Does it occur when you shut the camera off, or change modes? 

[strutzj]

Back button focus and live view focus is mutually exclusive in all modes (i.e. P, Av, Tv, M, etc.). I don't think this is a unique problem, other people have had the same problem according to online comments. Please grab a 5D Mark 4 and try it yourself. 

[Tim]

strutzj, 

I would grab a camera if that were a possibility but at this time our offices are actually closed due to a statewide lockdown order.  We regret any inconvenience that this may cause you at this time. 

[RobertTheFat]

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@Tim wrote:

strutzj, 

I would grab a camera if that were a possibility but at this time our offices are actually closed due to a statewide lockdown order.  We regret any inconvenience that this may cause you at this time. 

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Since I do have a 5D4 handy, I just tried it, and it appears to work for me. I was using the EF 24-70mm f/2.8L II lens. What exactly is the symptom that it's not working? Does it not focus? Does the shutter not fire?

FWIW, my camera is at firmware level 1.2.1, which I believe is the latest.

EDIT: I guess I wasn't in servo mode. Does that matter?

EDIT 2: Tried it again in AI Servo. Still seems to work.

[Waddizzle]

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@strutzj wrote:

Back button focus and live view focus is mutually exclusive in all modes (i.e. P, Av, Tv, M, etc.). I don't think this is a unique problem, other people have had the same problem according to online comments. Please grab a 5D Mark 4 and try it yourself. 

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Try resetting the camera back to factory defaults.  

Before you do, what focusing mode are you using in Live View.  Try switching back to the default setting.  There is one setting that focuses with the images sensor.  Another setting drops the mirror and focuses with the AF Sensor, just as you would if you were using the viewfinder.  This latter is the mode that you want.

[RobertTheFat]

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@Waddizzle wrote:

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@strutzj wrote:

Back button focus and live view focus is mutually exclusive in all modes (i.e. P, Av, Tv, M, etc.). I don't think this is a unique problem, other people have had the same problem according to online comments. Please grab a 5D Mark 4 and try it yourself. 

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Try resetting the camera back to factory defaults.  

Before you do, what focusing mode are you using in Live View.  Try switching back to the default setting.  There is one setting that focuses with the images sensor.  Another setting drops the mirror and focuses with the AF Sensor, just as you would if you were using the viewfinder.  This latter is the mode that you want.

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Whichever of those focusing modes I was using when it appeared to work for me, the camera did not drop the mirror.

[strutzj]

When configured for back button focus (AF-ON reconfigured for servo focus and shutter button configured for metering only) and I attemp to use live view focus, the shutter fires but focus doesn't move. Reprogramming the shutter button for normal operation (metering and focus), live view focus works fine (i.e. it focuses on the point of touch and the shutter fires).