Back button focus

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I added a little bit of Sugru to the back button of the Q which makes it easier to use it for back button fokus.

 

[stephanjaeger]

I added a little bit of Sugru to the back button of the Q which makes it easier to use it for back button fokus.

 

Brillant idea!

 

Stephan

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[Leica Guy]

Agree completely. That is exactly my rationale with Q and DSLR. Moreover, the ergonomics of the D800 and the position of the button fit my hand perfectly and in a way that is just not possible with Q with or without a Thumbs up, for perfectly understandable reasons. Not a complaint just an inescapable fact for me!

+1. Exactjy my thinking also. Really appreciate your explanation and logic.

[plasticmoz]

Folks, lets get to basics of why many DSLR users prefer BBF, particularly for wildlife, birds, and other fast moving subjects. I have been using BBF with my Nikon DSLRs for more than a decade now. One key issue to remember is that you can set your camera to AF-S or AF-C. Without BBF, depending on which one you set, half-pressing shutter will either focus once (AF-S) or will continue focusing for as long as it is half-pressed (AF-C). Now, there are some scenarios that this would be a problem:

 

1) Locking focus for consecutive shots: This will only be possible by locking the focus using the back button, or else consecutive shutter release will continue to focus again, regardless of AF-S or AF-C modes.

2) Focus and recompose: Without BBF, you can only do this with AF-S, and it will not be possible with AF-C.

3) Track focus: Without BBF, you can only do this with AF-C, and it will not be possible with AF-S.

 

Now while you are in the field taking pictures of wildlife and such, a lot of times you would want to switch, particularly between Scenarios 2 and 3 above, as quickly as you can. And instead of having to switch the mode from AF-S to AF-C and vice versa, it would be much quicker and more convenient if you decouple the shutter release from focusing, and instead use BBF. By doing that, you can leave your camera in AF-C all the time. And for scenario 2, you would just press the back button once and then release before recomposing, whereas for scenario 3, you would keep depressing the back button. 

 

Leica Q works exactly the same way, i.e., when on my Q, I change the back button mode to AFL, half-pressing the shutter button does NOT focus anymore. Technically I can still leave the focus mode on either AF-S or AF-C. In AF-S, pressing the back button will focus once even if you keep pressing it. And it will only refocus once you release the back button and press it again. And if AF-C, it will continue to focus for as long as you depress the back button. Again, similar to DSLR, when you are using BBF, in general, it no longer makes sense to leave the focus mode in AF-S. Because to achieve the single focus, you can simply press the back button once and release it. And when you want to track focus, you can simply continue depressing the back button. 

 

All that said, I have concluded that with my Leica Q, the focus accuracy and speed is much better in AF-S mode than in AF-C. As such, and given that I will rarely use my Q for wildlife and fast moving subjects, I have decided to NOT use BBF with my Q, and just leave it on AF-S most of the time. The fact that the back button is a bit inconvenient to use when a Thumbs Up is installed was another factor for me forgetting about BBF with the Q despite it being my strongly preferred way of focusing for many years with my Nikon DSLRs...

 

If any new owners are reading through this thread, this post pretty much summarizes the issues perfectly.