Back button focus - Is it still relevant with AF subject detection and tracking

[Camatose]

No. When I take my thumb off the BBF button all focussing ceases, ie focus is locked. Which, in the circumstances I described, is what I want to achieve, and which is one of the benefits of BBAF in those circumstances. If I want to refocus, thumb goes down, and if I don't want to refocus thumb stays up.

How is that different? When I take my finger off the shutter button, focus is locked. It won't try and focus further until I half press the button. I honestly see no difference here.

 

[Camatose]

Okay, so in that case you are dependent upon the subject/eye tracking to keep focus. I don't think that will handle the "grass waving in front of the animal" all the time and it won't work if I need to use something like single point because I'm not tracking, I'm saying "focus here."

I'm sure it works for you, I suspect BBAF is still a bit more flexible. Not necessarily better, but flexible. And BBAF is still needed and relevant because some people want to use it.

Negative, I rarely use subject tracking, just tracking in general. If I lock on a subject the camera will try to stay on it, no recognition needed. The camera doesn't need to recognize an airplane or automobile to lock on and track. But as previously stated, I've pretty much stopped using tracking for most of what I do.

 

[bleirer]

How is that different? When I take my finger off the shutter button, focus is locked. It won't try and focus further until I half press the button. I honestly see no difference here.

When you half press again as you describe, doesn't it focus on something new, rather than holding the focus lock?

 

[arbitrage]

Personal preference aside, the only real reason to use BBF on a MILC with 90+% AF coverage and reliable subject/object tracking modes is to allow MF through clutter that is distracting the AF (even the object tracking AF) and not trigger AF when you hit the shutter after you MF through said clutter.

If one likes shutter AF then the solution to that issue is to program a custom key to AF-OFF.

 

[Ken Miracle]

With DSLR’s, back button focus was the only option. This is because you would lock in the focus on the subject then re-compose the frame. However, I have started to wonder if this is still relevant with the new Z series and mirrorless cameras.

For most things, I now shoot AF subject detection. When using the subject detection, the focus tracks with the subject where ever it is in the frame. The focus stays on the subject and I can recompose all day long, never needing the back button focus.

For focus locking I can see where this may still be relevant ie. waiting for a subject to appear in a blank area, but this is rare for me in sports photography and some wildlife.

What benefit is it to still use back button focus or is it no longer relevant with AF subject detection and tracking.

I am a bird photographer, hiking in all types of terrain never know what bird will show up and when.

LOL I tried BBF with DSLR's for almost a year and in the long run I found it to be slower and less efficient for me. For me I could never get my head around haviing to push two buttons to take a photo. I just moved the focus point to where I wanted with my thumb and for me it was faster and more efficient.

Irony now with Z9 I use 3 forms of BBF (or FBF) ... basics AF-C and manual with auto ISO and subject detection - bird on all of the time when birding but with button programmed to toggle subject detection on and off.

I usually have my shutter release set to wide area custom 5x3 if I encounter a situation where I want to go directly to 3D AF I have my AF-ON button programmed to 3D AF + AFon.

I have FN1 set to wide area custom 1x1 + AFon

I have FN2 set to Auto Area AF + AFon

And then there are times now with fw 5.0 being able to program a button .. I use video record button .. to toggle through the 4 AF Area modes mentioned above plus old fashioned single point. If I know what AF Area mode I will most likely use first then I toggle that to be on my shutter button .. most common being AF Area Mode when I expect BIF in relatively uncluttered habitat.

 

[Anthony]

Personal preference aside, the only real reason to use BBF on a MILC with 90+% AF coverage and reliable subject/object tracking modes is to allow MF through clutter that is distracting the AF (even the object tracking AF) and not trigger AF when you hit the shutter after you MF through said clutter.

If one likes shutter AF then the solution to that issue is to program a custom key to AF-OFF.

 

[ccirelli]

I basically set up what I call "reverse BBAF" meaning I just set AF-ON to be a focus lock, instead of activating AF. So now instead of needing two fingers 95% of the time, now I just need two fingers 5% of the time. My thumb is free'd up for other things, or, just to hold the camera. I also shoot one-handed quite a bit (portrait and macro, where my left hand is holding a light or reflector, steadying a branch, etc.). One-handed shooting is so much easier / steadier when I don't need to constantly press AF-ON, my thumb can just hold the body.

In my action bank / setup I used to keep AF-ON set to activate 3D Tracking, for that hand-off technique. But I've found with Nikon's latest firmware updates, that technique (for me) has become almost obsolete (auto area is really good now!).

Also on my Z8, there are so many other ways to instantly change AF modes, or just turn off Subject Detection instantly if it's having a confused moment. I can set a function button to immediately switch to Single Point + AF-ON activation, which is really handy. Another custom button can be 3D tracking + Subject Detection OFF, etc.

My goal is to keep things as simple as possible, without sacrificing any control. Hope this helps / makes sense.