Back button focus with eye/face/body detection (SL2, SL2-S, SL3, SL3-S)

[LD_50]

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I've seen this asked before but I want to ensure I'm not missing an updated answer. I'm shooting with an SL2-S but this could apply to SL2, SL3, SL3-S as well. 

Goal:

Decouple the shutter from focus activation. Use all focus options by pressing and holding the joystick button.

Settings:

Customize Control--> Joystick --> MF Mode --> AFc

Customize Control--> Joystick --> Button Lock --> Press and Hold

AF Mode --> Eye/Face/Body Detection

Focus Mode --> MF

Results:

Pressing the joystick activates autofocus in AFc, using eye/face/body detection. 

It does not allow for selection of which face to focus on, which would require movement of the joystick left, right, up, or down.

It does not allow for selection of which eye to focus on (normally controlled by pressing the joystick when a face is identified). 

Failed Work-around:

I tried the following, but it did not work:

Customize Control--> Joystick--> Button Lock--> Double Press

This turns on AFc with one press of the joystick button, and shuts it off with another. With AF mode--> Eye/Face/Body Detection set, a press of the joystick turns on the detection, but it still does not allow for selection of the face to focus on. 

I thought this may work because it doesn't require you to hold the joystick button, but as soon as you select left, right, up, or down, it shuts off AFc as if you'd pressed the button.

Workaround with no back button focus control:

To allow selection of the face to focus on, I've found the only way to achieve this is to change settings to:

Focus Mode --> AFc

This then makes a half-press of the shutter turn on eye/face/body detection and allows for the joystick to control which face to focus on. 

The joystick button is then only allowed to control AF-L, AE-L, or AF-L + AE-L but not activating AF.

 

Has anyone found a setting I've missed that allows for back button (joystick) focus activation and still allows for selection of a specific face using the joystick? 

I've been dealing with this for a long time but it's frustrating to have to go back to shutter control whenever I want to use eye/face/body detection. 

Edited January 20 by LD_50

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[hoolyproductions]

Hi. Just to say that I have not either found a way to do this. I rarely use AF-C and when I do I don't mind using AF-S mode. I agree this would be a nice to have, if it could be implemented well.

[Luke_Miller]

I can set up my Nikon Z8 that way, since it has a dedicated AF-On button and a separate joystick to select the face/eye I want. But even with the Z8 I don't use face detection.  I've been using autofocus since Nikon's introduction of it in the F4 film body I bought in 1990 and so am used to placing an autofocus point on my subject rather than have the camera detect the subject.  With both my Z8 and SL2 bodies I find face/eye detect interupts my shooting due to picking or jumping to a non-subject and forcing me to manage the autofocus system rather than concentrate on getting the shot.

Instead I use AFC and Tracking mode with both systems.  That way I can place the tracking box on the subject then engage autofocus (with the joystick or AF-On button depending on camera) and track the subject while composing the shot.  Since I still use both camera systems I want to have a common autofocus setup so I don't have to think about which brand I have in my hand.  The above is the  only setup I have found that works with both for me.  The one change I had to make with my Nikon after adding the Leicas was due to the difference between Nikon and Leica when the AF-On button (Nikon) or joystick (Leica) is released. In AFC the Nikon locks the focus while the subject is in-focus when I discontinue autofocus while the Leica does not much of the time. So to make my AF settings work across both systems I keep autofocus engaged while taking the shot, even with static subjects.

I am always interested in the posts that disparage AFC performance of the SL cameras, since every shot I take with mine (SL, SL2, SL-2S) is in AFC. As an event shooter my shooting does not require state-of-the-art autofucus performance.  My Leicas handle coming down the aisle wedding shots and occasional children running or on a water slide without issue. So SL camera AFC is sufficient to my needs.  In the rare situation when I need more I have the Z8.

Edited January 20 by Luke_Miller

[LD_50]

I only use eye/face/body detection when there are not a lot of subjects to distract it. 

At this point I go back to AFc mode to make it work. My normal setup is MF mode and spot or field focus.

I also came from Nikon, and used the AF On button to engage AF there. I also shoot in AFc with both systems. I do think Leica’s implantation has been way behind others’, at least through the SL2-S. 

If I recall correctly, Z8 joystick can be set to activate AF if you want the same functionality as Leica. You could then assign AF-On button to something like 3D tracking or subject detection. 

[Smogg]

Therefore, the next firmware needs fast profile switching for SL3 and Q3 28/43. Considering the unreliability of people recognition, it would be possible to try face detection and, in case of failure, quickly switch to another profile. Slow switching between profiles now forces us to use only what works reliably: AF-S at the central point.

[Photoworks]

8 minutes ago, Smogg said:

Therefore, the next firmware needs fast profile switching for SL3 and Q3 28/43. Considering the unreliability of people recognition, it would be possible to try face detection and, in case of failure, quickly switch to another profile. Slow switching between profiles now forces us to use only what works reliably: AF-S at the central point.

you can use the Toggle Focus Point.

[LD_50]

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1 hour ago, Smogg said:

Therefore, the next firmware needs fast profile switching for SL3 and Q3 28/43. Considering the unreliability of people recognition, it would be possible to try face detection and, in case of failure, quickly switch to another profile. Slow switching between profiles now forces us to use only what works reliably: AF-S at the central point.

I don’t use profiles. I do have a button set to change AF from face/eye/body detection to field or spot. I have another set to change from MF to AFc. If there were fast profile switching, I might consider using it. 

[Smogg]

1 hour ago, Photoworks said:

you can use the Toggle Focus Point.

I already sold the SL3 and can't check, but as far as I remember, these only work for one frame

[Photoworks]

26 minutes ago, Smogg said:

I already sold the SL3 and can't check, but as far as I remember, these only work for one frame

You can have Face/body, tub the button and it switches to center field, and you can keep switching it all day long

[Jean-Michel]

To LD_50

Your 'workaround' in your original post is not a workaround, it is simply the correct way to use the camera with body/face detection on.

When you use the body/face detection mode, you let the camera find and focus on the body or face that is probably the closest to the camera. You cannot have both the camera and yourself fight over where to focus. The back button does allow you to move the focus boxes from, for example left to right eye, or person 1 to person 2.

I find that body/face detection works quite well, but I still prefer to simply use spot focus and the back button for just about anything. Then again, I do not photograph high speed sports or such, and if I were to be in that business I would use a totally different camera system. 

[LD_50]

1 hour ago, Jean-Michel said:

To LD_50

Your 'workaround' in your original post is not a workaround, it is simply the correct way to use the camera with body/face detection on.

When you use the body/face detection mode, you let the camera find and focus on the body or face that is probably the closest to the camera. You cannot have both the camera and yourself fight over where to focus. The back button does allow you to move the focus boxes from, for example left to right eye, or person 1 to person 2.

I find that body/face detection works quite well, but I still prefer to simply use spot focus and the back button for just about anything. Then again, I do not photograph high speed sports or such, and if I were to be in that business I would use a totally different camera system. 

It’s a workaround. I set up the camera to MF mode. I set the joystick to activate AFc. AF mode is face/eye/body detection. This all works.

What does not work is the ability to then select which face/eye/body because they didn’t include any other way to do it and with this set up the joystick is already in use. 

Even if you set the joystick to “turn on” AFc and leave it running, it will not work to activate face/eye/body and allow selection with the joystick. It treats any movement of the joystick as a center button press and shuts off the AF. This is inconsistent with other modes. 

[Jean-Michel]

There are any number of ways to set up the functions of the camera. I gather that you do not use back-button focusing.

One way, is to set the back button for focusing, on both AF modes and MF. But, as you found out, if you then set the focus mode to body/face detection, the back button is no longer able to focus, you need to half-press the shutter button for that; and the joystick is used to move the focus boxes around.

[Photoworks]

2 hours ago, LD_50 said:

This is inconsistent with other modes. 

SL? Q3?

[LD_50]

2 hours ago, Jean-Michel said:

There are any number of ways to set up the functions of the camera. I gather that you do not use back-button focusing.

One way, is to set the back button for focusing, on both AF modes and MF. But, as you found out, if you then set the focus mode to body/face detection, the back button is no longer able to focus, you need to half-press the shutter button for that; and the joystick is used to move the focus boxes around.

You must not be reading my description and detailed setup. I AM using back button focus where the joystick press activates AF. The camera is in MF mode for this. 

Back button focus decouples the shutter release from AF activation. 

In this example Leica added face/eye/body detection but in the process didn’t maintain the ability to use the functionality while also using back button focus. The joystick is assigned to two functions with setup, leaving one only functioning partially. 

[LD_50]

42 minutes ago, Photoworks said:

SL? Q3?

SL2-S is what I’m using.