Has back button autofocus outlived its usefulness?

[Luke_Miller]

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I've used the back button autofocus technique for over 15 years with my DSLRs and now the SL bodies.  Currently I am set up in AF-C and Dynamic (Tracking) mode with autofocus on the joystick and that works well for me.  My SL2 appears to work well in face detect mode which appeals to me as an event shooter.  Unfortunately, by assigning autofocus to the joystick I lose the ability to change the face (or eye) being focused on if it is not the one I want.  Is it time to move on from back button autofocus?

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[SrMi]

For me, BBF is still the most flexible way to photograph.

For still subjects, I prefer to separate the focusing operation from exposure and composition. I hate it when the camera refocuses when pressing the shutter.

For active subjects, BBF or shutter button focusing is equally useful, but I keep it at BBF. As an event shooter, you may need to give up BBF because of the tradeoff you described, not because BBF is no longer helpful.

 

[Robert E]

Quote

 Is it time to move on from back button autofocus?

I never could understand why some like this method?  I tried it for a while and did not care for it at all, why create a second step just to focus? It's so much easier just to push the shutter button down half-way, after all, your finger is already there. Why create more movement back and forth doing a two step process just to focus? Still seems silly to me, but that's just my opinion. I much rather use the shutter button half way, after all, that's why they put that feature into the camera, to make focusing easier. 🙂

[Luke_Miller]

8 minutes ago, Robert E said:

I never could understand why some like this method? 

It is a solution to a specific problem where one's subjects can quickly change from static to moving.  It allows the camera to remain in AF-C for moving subjects (keep pressing the joystick) or press, gain focus and release on static ones.   Effectively either AF-C or AF-S without having to change settings.  It became a "thing" in the DSLR world.  Now with mirrorless its use is evolving.

[SrMi]

32 minutes ago, Luke_Miller said:

It is a solution to a specific problem where one's subjects can quickly change from static to moving.  It allows the camera to remain in AF-C for moving subjects (keep pressing the joystick) or press, gain focus and release on static ones.   Effectively either AF-C or AF-S without having to change settings.  It became a "thing" in the DSLR world.  Now with mirrorless its use is evolving.

It also combines the flexibility of MF, i.e, you decouple capture from focusing.

[geronimosan]

2 hours ago, SrMi said:

For me, BBF is still the most flexible way to photograph.

For still subjects, I prefer to separate the focusing operation from exposure and composition. I hate it when the camera refocuses when pressing the shutter.

For active subjects, BBF or shutter button focusing is equally useful, but I keep it at BBF. As an event shooter, you may need to give up BBF because of the tradeoff you described, not because BBF is no longer helpful.

 

Many did/do it for separation of scene exposure/metering and subject autofocus.  For example, if you want the scene metered on the flame of a candle but want the focus sqaure on a dark object sitting on a table illuminated by the candlelight.  Half-press for metering, move autofocus square, use BBF to grab focus elsewhere, take picture.

[Paul2660]

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It's also very helpful when shooting a pano (multi image series) or in Low light.  The SL2 is not the best at hitting accurate focus in low light, foggy sky, afterglow sunset etc. So if you hit the back focus and now know it's accurate, you can shoot unlimited number of frames without worry.  With a Pano, especially one you are shooting handheld, it very possible that on one or more frames, the focus point will either hit on sky or dark area of the subject, thus it will hunt and possibly miss, so the series of images needs to be re-shot.  With BBF, I will hit are areas I know the camera can lock focus on, the shoot the series of images.  It helps if you are on a tripod also, as many times you don't have the time to re-acquire the focus due to changing light. 

 

Paul C 

[Jptsr1]

I stopped using it when I switched from the Sony A7III to the Canon R6. Autofocus and metering on the R6 was/is at the point where I didn't feel I needed it anymore. Not so much the case with my SL2 but now I'm used to not using BBF so I didn't switch back (I tried but it felt weird after years of not using it). 

[Smogg]

10 hours ago, Robert E said:

I never could understand why some like this method?  I tried it for a while and did not care for it at all, why create a second step just to focus? It's so much easier just to push the shutter button down half-way, after all, your finger is already there. Why create more movement back and forth doing a two step process just to focus? Still seems silly to me, but that's just my opinion. I much rather use the shutter button half way, after all, that's why they put that feature into the camera, to make focusing easier. 🙂

When you shoot on the street, you very often need prefocus on a certain point, since the main composition (background, middle ground) is already built, but you wait for an event at a certain point in space for quite a long time (it can be half an hour). You'll just get tired of holding the shutter button half-pressed for so long

[robb]

That’s the only way I shoot every camera…

so I’d always like that option.

Robb

[Smogg]

2 minutes ago, robb said:

That’s the only way I shoot every camera…

so I’d always like that option.

Robb

I have the same approach. If the camera does not have the ability to configure BBF, then I will not even consider buying such a camera (example Q3)

[hoolyproductions]

In addition to all the reasons above, I started using BBF when shooting music gigs in low light where there can be some lag (with any camera) in aquiring focus. Often I set the focus e.g. just behind the microphone and wait for a moment when the singer has a more expressive/ecstatic stance (if I wait for focus aquisition the moment will be gone). Now I use it 99% of the time e.g. also for candid landscapes and panoramas for the reasons outlined above.  

[Stuart Richardson]

It is also much more convenient if you want to make several different photos of the same scene, but do not want the focus point to change. It is extremely useful for night photography, where most of the time your focus lock will go all over the place as it hunts. With BBF you can focus on a bright star, the moon, a streetlight etc and then the focus point will stay there. It will do this much faster than manual focus alone. Essentially it is like a kind of manual focus plus. AF cameras these days tend to have less than ideal manual focus mechanisms. Focus by wire tends not to feel great and does not have any haptic feedback like a real manual focus lens. Accuracy is hard to ensure without enlarging the image, which a lot of cameras do automatically. But that disrupts composition. I find that back button focus allows me to quickly and accurately define a focal point and then allow me to focus on composition. I am not the kind of photographer who found much need to use AFc or tracking, but I am glad it is there for people who need it. I think back button focus is probably the same. For me it is an extremely useful method of working.

Edited April 25, 2024 by Stuart Richardson

[Coral Palm]

To me the beauty of BBF on the SL is I can move the focus point around via toggle, press the toggle to nail focus, then activate the shutter with the button on top. It has been years but if I recall with Nikon/Canon it was two different buttons, one to move focus point and another to focus.

[Luke_Miller]

21 minutes ago, Coral Palm said:

It has been years but if I recall with Nikon/Canon it was two different buttons, one to move focus point and another to focus.

Yes, with my Nikon bodies there is an AF-On button that initiates autofocus. There is also a joystick that allows one the move the focus point or select a different face/eye (when in face detect) than the one the camera selected.  My problem with using face detect on my SL2 is that I have not found a way to change the camera selected face or eye if using the joystick to autofocus.

[SrMi]

2 minutes ago, Luke_Miller said:

Yes, with my Nikon bodies there is an AF-On button that initiates autofocus. There is also a joystick that allows one the move the focus point or select a different face/eye (when in face detect) than the one the camera selected.  My problem with using face detect on my SL2 is that I have not found a way to change the camera selected face or eye if using the joystick to autofocus.

The problem is not whether BBF has outlived its usefulness but that you have to choose between BBF and face selection. It's a tough choice.

[Luke_Miller]

32 minutes ago, SrMi said:

The problem is not whether BBF has outlived its usefulness but that you have to choose between BBF and face selection. It's a tough choice.

Apparently so.   I'm trying to avoid setting up my SL bodies differently than my Nikon Z8.  I suspect I will not be using face detect on the SL/SL2. 🙁

[Dr. G]

I've always used it so I continued to do so on the SL3.  The only thing I find is that the joystick on the SL3 seems very sensitive so it's easy to move the focus point while trying to depress it for focusing.  

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Hallo,

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