Back Button focussing on Nikon Z5?

[Frank B]

Hello. Firstly, I am a newbie and this is my first question.

I use a Nikon D610 and am currently thinking of buying a Nikon Z5 (mirrorless). I use back button focussing on the D610. Am I right in assuming, after seeing Steve's videos "Is it time to ditch your DLSR?" and "Mirrorless Advantages and Disadvantages" that back button focussing is irrelevant on the Nikon Z cameras because of AF allover with the Z series of cameras?

Regards

Frank

 

[DRwyoming]

Hello. Firstly, I am a newbie and this is my first question.

I use a Nikon D610 and am currently thinking of buying a Nikon Z5 (mirrorless). I use back button focussing on the D610. Am I right in assuming, after seeing Steve's videos "Is it time to ditch your DLSR?" and "Mirrorless Advantages and Disadvantages" that back button focussing is irrelevant on the Nikon Z cameras because of AF allover with the Z series of cameras?

Regards

Frank

I still use BBAF on my Z6II, it's not as necessary as it might have been with DSLRs since the focus points cover almost the entire screen so there's no need to use focus-reposition shooting for dramatically off center focus points. That said I still prefer BBAF as I want to focus when I want to focus and don't want the camera to automatically start an AF cycle every time I half press the shutter release. IOW, I really like having focusing on-demand when I want it but only when I want it and BBAF does that nicely. But I know plenty of photographers that either never went to BBAF or went back to shutter release focusing with their switch to mirrorless so it's really up to you and your shooting preferences.

 

[Frank B]

Thanks for your response, DR - appreciated

 

[bleirer]

To add a question to your question, some here say that they use bbaf because you lose some tracking ability with the shutter half press. For example if you shoot a short burst and release you then have to re-acquire the focus target, where with bbf they say you stay on the target all through and after the short burst.

My question is whether this is truly a difference between bbf and shutter half press? And how does the camera do it with the shutter opening and closing? Wouldn't it lose the target any time the shutter closed no matter which focusing method?

 

[DRwyoming]

To add a question to your question, some here say that they use bbaf because you lose some tracking ability with the shutter half press. For example if you shoot a short burst and release you then have to re-acquire the focus target, where with bbf they say you stay on the target all through and after the short burst.

My question is whether this is truly a difference between bbf and shutter half press? And how does the camera do it with the shutter opening and closing? Wouldn't it lose the target any time the shutter closed no matter which focusing method?

I hadn't heard of that rationale for using BBAF, mostly I either hear folks saying they don't need it with the wide spread of AF points across the viewfinder or with the flagship cameras they'd prefer to allocate that back button to some other important function like toggling eye tracking or another focus mode.

Conceptually it's really hard to imagine that activating AF with the back button is fundamentally different than activating AF with a half press on the shutter release in terms of subject acquisition or tracking.

In terms of AF blackout periods, this is definitely a thing with mechanical shutters and slower readout sensor designs but I wonder if it's less of an issue with fast electronic shutters and dual readout sensors that send sensor data to the AF module and image processing at the same time. I really don't know, just thinking out loud here but I could imagine the latest batch of stacked sensors and new data flow architectures has made shutter blackout and its impact on AF tracking less of an issue.

My main reason for sticking with BBAF on my mirrorless camera is for relatively static subjects like macro and landscapes or astro work where I want to set the focus and not have the camera try to reacquire focus every time I touch the shutter release. Sure I could switch to manual focus on the lens or camera body but with BBAF the camera basically defaults to manual focus mode yet I have full AF available on demand with a simple thumb press. I just like operating that way. But sure, if and when I end up with a top end mirrorless camera and want extra controls dedicated to the high end tracking or eye detect modes I might find that back button has better uses.

 

[Patrick M]

I’d imagine using the shutter to focus, for continuous shooting, would mean partially depress to focus, fully press to shoot, then release and partially depress to reacquire focus.
with BBF you’re always holding the focus button, so its faster reacquiring focus.

 

[bleirer]

I’d imagine using the shutter to focus, for continuous shooting, would mean partially depress to focus, fully press to shoot, then release and partially depress to reacquire focus.
with BBF you’re always holding the focus button, so its faster reacquiring focus.

So in your view the bbf is also re-acquiring focus after a burst, not holding it through the burst?

 

[bleirer]

I hadn't heard of that rationale for using BBAF, mostly I either hear folks saying they don't need it with the wide spread of AF points across the viewfinder or with the flagship cameras they'd prefer to allocate that back button to some other important function like toggling eye tracking or another focus mode.

Conceptually it's really hard to imagine that activating AF with the back button is fundamentally different than activating AF with a half press on the shutter release in terms of subject acquisition or tracking.

In terms of AF blackout periods, this is definitely a thing with mechanical shutters and slower readout sensor designs but I wonder if it's less of an issue with fast electronic shutters and dual readout sensors that send sensor data to the AF module and image processing at the same time. I really don't know, just thinking out loud here but I could imagine the latest batch of stacked sensors and new data flow architectures has made shutter blackout and its impact on AF tracking less of an issue.

My main reason for sticking with BBAF on my mirrorless camera is for relatively static subjects like macro and landscapes or astro work where I want to set the focus and not have the camera try to reacquire focus every time I touch the shutter release. Sure I could switch to manual focus on the lens or camera body but with BBAF the camera basically defaults to manual focus mode yet I have full AF available on demand with a simple thumb press. I just like operating that way. But sure, if and when I end up with a top end mirrorless camera and want extra controls dedicated to the high end tracking or eye detect modes I might find that back button has better uses.

On my Canon I've gotten in the habit of using shutter half press but using a back button to turn off af when held for recomposing. Though I do have another custom mode set to bbf for landscape or macro on a tripod where it is awkward to hold the button.

 

[Patrick M]

So in your view the bbf is also re-acquiring focus after a burst, not holding it through the burst?

That’s my thinking. There‘s a setting that one uses that can alter the delay before the camera acquires focus to allow, for example, something blocking a moving target momentarily. This suggests some logic built in to accommodate the shutter blackout. So even while continuous pressing the AF-On there’s a loss of focus that needs reacquiring

 

[bleirer]

That’s my thinking. There‘s a setting that one uses that can alter the delay before the camera acquires focus to allow, for example, something blocking a moving target momentarily. This suggests some logic built in to accommodate the shutter blackout. So even while continuous pressing the AF-On there’s a loss of focus that needs reacquiring

In that case I think I will stick with shutter half press for focusing and a back button to lock focus for occasional recomposing.