Back button focus

[Guest NEIL-D-WILLIAMS]

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Is the metering lock the same as Back Button Focus like on a DSLR??

Can you use the thumb button to activate AF and then recompose and take the picture like you can on the Leica S

Thanks Neil

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[Herve5]

On the Q you can se the thumb button to either activate and lock focus, activate and lock exposure, or both at the same time.

So yes, by setting it to lock focus only, you can press thumb, then recompose and tale the picture, with additionally an updated exposure.

This moreover can be recorded along with all other parametered buttons into a specific profile, and you may have different ones ("museum", "nature", "street"...). Not sure you can actually name them though, have to try

[wda]

Either lock focus or exposure is useful, but cannot see a use for both, although I guess some users might.

[Guest NEIL-D-WILLIAMS]

I use it on my Leica S and Nikon gear with focus lock............ I will try and do the same on the Q when I get it

[Orguy]

Is the metering lock the same as Back Button Focus like on a DSLR??

Can you use the thumb button to activate AF and then recompose and take the picture like you can on the Leica S

Thanks Neil

 

Here is a discussion of BBF and how to set it up in the Q (at the bottom of article),  like you expect to operate on an SLR (including continuous focussing),

 

http://streetist.uk/tag/bbf/

 

I have tried this and have mixed feelings. I see the advantages of BBF, but I will have to get used to using the thumb button rather than the shutter button for focus. The problem is that due to the DOF with a 28mm lens, you sometimes don't immediately see that you forgot to focus before pushing the shutter. When focus control is on the shutter button, you are forced to focus before taking picture. Anyone else have comments and experience about this? 

[Herve5]

I have tried this and have mixed feelings. I see the advantages of BBF, but I will have to get used to using the thumb button rather than the shutter button for focus. The problem is that due to the DOF with a 28mm lens, you sometimes don't immediately see that you forgot to focus before pushing the shutter. When focus control is on the shutter button, you are forced to focus before taking picture. Anyone else have comments and experience about this? 

Why do you want to change? Keep both!

Setting the thumb button to focus trigger + lock doesn't remove this function from the shutter half-press.

I do keep focus on the shutter, and the thumb button in parallel allows me to lock focus only when I need...

Edited February 14, 2016 by Herve5

[Guest NEIL-D-WILLIAMS]

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Thank you sir

[Guest NEIL-D-WILLIAMS]

Why do you want to change? Keep both!

Setting the thumb button to focus trigger + lock doesn't remove this function from the shutter half-press.

I do keep focus on the shutter, and the thumb button in parallel allows me to lock focus only when I need...

That doesn't sound right to me. Normally when you assign BBF the shutter release no longer activates the focus. If it did, then when you press the BBF and let go to recompose like you should do, but now you go and try to take a picture the camera will refocus again wherever the single focus point is looking at............

No good

[Herve5]

That doesn't sound right to me. Normally when you assign BBF the shutter release no longer activates the focus. If it did, then when you press the BBF and let go to recompose like you should do, but now you go and try to take a picture the camera will refocus again wherever the single focus point is looking at............

No good

No, the way I see it here is, when I use the thumb button (if set this way) it does lock the focus as long as I press it, including when I press the shutter.

When I don't use the thumb button, the shutter works as it should : focussing when half-pressed.

And the same behavior would happen if I did set the thumb button to exposure lock, or exposure + focus : lock the thing for as long as the thumb button is depressed, otherwise, leave it to the shutter to do the job as usual.

[Guest NEIL-D-WILLIAMS]

No, the way I see it here is, when I use the thumb button (if set this way) it does lock the focus as long as I press it, including when I press the shutter.

When I don't use the thumb button, the shutter works as it should : focussing when half-pressed.

And the same behavior would happen if I did set the thumb button to exposure lock, or exposure + focus : lock the thing for as long as the thumb button is depressed, otherwise, leave it to the shutter to do the job as usual.

 

Sorry mate your wrong.......I don't have the Leica Q but I have the Leica S and when the BBF is set correctly the shutter button DOESN'T activate the focus whether it is half pressed or fully pressed.............I can speak for the Q as I won't get it until Friday

[Herve5]

Sorry mate your wrong.......I don't have the Leica Q but I have the Leica S and when the BBF is set correctly the shutter button DOESN'T activate the focus whether it is half pressed or fully pressed.............I can speak for the Q as I won't get it until Friday

Well, I have the Q and can repeat : the way I describe is what happens. So, well, I'm not wrong, specially in front of someone not having the camera :-)

Again:

- I have the thumb button set to focus lock

- when I press this button, well, the autofocus starts, sets the focus and locks

- then whatever I aim (as long as I maintain the thumb button depressed), the focus stays locked, until and including when I shoot

- if I release (or just don't use) the thumb botton, then the shutter button naturally takes back control, and a half-press on it will focus and lock -as expected, I dare say.

Edited February 14, 2016 by Herve5

[Gatville]

I have the back button assigned to AF on my Q and in this mode the shutter has no affect on focus, whether or not I have pressed the back button.

[marchyman]

BBF may work as Herve5 describes IFF you are using AFc.   Not everyone uses BBF that way.   If you use AFs pressing the back button causes the camera to focus and give you an indication beep if so enabled.   A later half press on the shutter does NOT change the focus.  It will, however, lock the exposure at whatever the camera is pointing.  You can then recompose again before completing the button press to take the image.

 

I go back and forth on using BBF in continuous vs single focus mode.   I'm currently using single mode on the Q and continuous on my DSLR.

[Guest NEIL-D-WILLIAMS]

I have the back button assigned to AF on my Q and in this mode the shutter has no affect on focus, whether or not I have pressed the back button.

 

Yes sir you have it set correctly

Well, I have the Q and can repeat : the way I describe is what happens. So, well, I'm not wrong, specially in front of someone not having the camera :-)

Again:

- I have the thumb button set to focus lock

- when I press this button, well, the autofocus starts, sets the focus and locks

- then whatever I aim (as long as I maintain the thumb button depressed), the focus stays locked, until and including when I shoot

- if I release (or just don't use) the thumb botton, then the shutter button naturally takes back control, and a half-press on it will focus and lock -as expected, I dare say.

You need to get yours setup the same way Gatville has his set up........... as yours is not how BBF is meant to work!!!!

[Herve5]

You need to get yours setup the same way Gatville has his set up........... as yours is not how BBF is meant to work!!!!

If I understand you correctly, I have to abandon the setup that works for me, with the AF mode I want, and adopt yours that doesn't work, and with an AF mode that I don't want.

Because it is "how it is meant to".

I retain the advice, and I suggest we close this discussion here, that'll save you exclamation marks.

At least the OP knows what is possible, which after all was the purpose of the thread.

[Guest NEIL-D-WILLIAMS]

If I understand you correctly, I have to abandon the setup that works for me, with the AF mode I want, and adopt yours that doesn't work, and with an AF mode that I don't want.

Because it is "how it is meant to".

I retain the advice, and I suggest we close this discussion here, that'll save you exclamation marks.

At least the OP knows what is possible, which after all was the purpose of the thread.

 

Don't close it yet we haven't finished arguing yet :)

[stantius]

This is what I found (Firmware 1.1):

 

Scenario A

- Zoom/Lock-Button: AFL

When I press the back button the camera will AF, I don't have to hold it

When I (half-)-press the shutter, the focus does not change

 

Scenario B

- Zoom/Lock-Button: AEL/AFL

When I use the back button the camera will AF and measure exposure

If I want to keep the settings, I have to keep pressing the backbutton otherwise the camera will re-focus and re-measure when (half-)pressing the shutter.

 

Scenario C:

- Zoom/Lock-Button: AEL

When I use the back button the camera will measure exposure

If I want to keep the setting, I have to keep pressing the backbutton otherwise the camera will re-measure when (half-)pressing the shutter.

Pressing the shutter will AF

 

Everybody is right

 

 

 

 

No, the way I see it here is, when I use the thumb button (if set this way) it does lock the focus as long as I press it, including when I press the shutter.

When I don't use the thumb button, the shutter works as it should : focussing when half-pressed.

And the same behavior would happen if I did set the thumb button to exposure lock, or exposure + focus : lock the thing for as long as the thumb button is depressed, otherwise, leave it to the shutter to do the job as usual.

[Tim B]

*****

 

Scenario C:

- Zoom/Lock-Button: AEL

When I use the back button the camera will measure exposure

If I want to keep the setting, I have to keep pressing the backbutton otherwise the camera will re-measure when (half-)pressing the shutter.

Pressing the shutter will AF

*****

And this is the reason why I have given up on trying to use the Back Button for AE Lock. It is only locked whilst the button is pressed. On every other camera I have used AEL means AE locked until the button is pressed again, which I find very useful. But I cannot continue to hold until shutter release, mainly because I am left eyed and my thumb gets in the way of my head! I gave up, but I haven't retried since updating to Firmware 1.1 - has this changed?

 

I am very disappointed at this implementation of AEL, perhaps the only thing I can find real fault with on the 'Q.' It actually feels like a firmware bug, but who knows what the programmers were thinking!

 

I haven't used the Back Button for AFL, because I'd rather lock exposure and reframe to focus.

 

Tim

Edited February 15, 2016 by Tim B

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Hallo,

Look here: Leica Q

[lucerne]

*****

 

Scenario C:

- Zoom/Lock-Button: AEL

When I use the back button the camera will measure exposure

If I want to keep the setting, I have to keep pressing the backbutton otherwise the camera will re-measure when (half-)pressing the shutter.

Pressing the shutter will AF

*****

And this is the reason why I have given up on trying to use the Back Button for AE Lock. It is only locked whilst the button is pressed. On every other camera I have used AEL means AE locked until the button is pressed again, which I find very useful. But I cannot continue to hold until shutter release, mainly because I am left eyed and my thumb gets in the way of my head! I gave up, but I haven't retried since updating to Firmware 1.1 - has this changed?

 

I am very disappointed at this implementation of AEL, perhaps the only thing I can find real fault with on the 'Q.' It actually feels like a firmware bug, but who knows what the programmers were thinking!

 

I haven't used the Back Button for AFL, because I'd rather lock exposure and reframe to focus.

 

Tim

 

Agreed Tim, but the same doesn't seem to apply to AFL, which retains lock without the need to hold the button so is useful for re-framing. However, I use neither of the features.

Edited February 15, 2016 by lucerne

[bkgs]

My experiments with this technique seem to indicate that when set as suggested pressing the thumb button locks the focus and the focus point remains set until the thumb button is pressed again or until the camera is turned off.  The "normal" press and focus using the shutter release does not resume until the camera is turned off and on again.