How you enable back button focus with Panasonic 70-200f4 with SL2

[ZHNL]

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As title, I’d pull the focus ring down to enable manual focus, SL2 AF was disabled even you set it manual focus mode with back button focus. 
if I pull focus ring up, the lens become AF only, you can’t enable Manual focus in SL2 menu, so you can’t decouple shutter from AF.

I don’t remember for sure, but I think sigma 45mm seems works as is.  put lens in manual mode, back button still works. I will double check. 

[thighslapper]

I'm sure more of these quirks will pop up. 

Leica should really implement a proper global 'decouple AF from the shutter button' that is independent of other settings. 

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[SrMi]

Sigma 45 and SL work fine. AF/MF is switched on the lens. In MF mode, back button focusing works.
Can someone confirm that back button focusing does not work when using 70-200 f/4 with SL/SL2? That would make that lens impractical to many SL/SL2 owners.

[chicagophoto]

6 minutes ago, SrMi said:

Sigma 45 and SL work fine. AF/MF is switched on the lens. In MF mode, back button focusing works.
Can someone confirm that back button focusing does not work when using 70-200 f/4 with SL/SL2? That would make that lens impractical to many SL/SL2 owners.

It also doesn't work with the Panasonic L mount 50mm 1.4 , focusing is only active by the shutter release. It might be a firmware update is needed but so much for a Leica certified product at this time.

[SrMi]

8 minutes ago, chicagophoto said:

It also doesn't work with the Panasonic L mount 50mm 1.4 , focusing is only active by the shutter release. It might be a firmware update is needed but so much for a Leica certified product at this time.

Thanks for the information. Hopefully someone filed a bug with Leica. I assume the issue is only with Lumix lenses that use the clutch to switch between AF and MF. Bummer.

[Chaemono]

vor 3 Stunden schrieb SrMi:

Thanks for the information. Hopefully someone filed a bug with Leica. I assume the issue is only with Lumix lenses that use the clutch to switch between AF and MF. Bummer.

No BBF implementation can work with the Lumix 50/1.4 S simply because to put that lens into MF one has to pull back the ring at the front of the lens barrel.  This deactivates the AF motor. 

[SrMi]

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5 minutes ago, Chaemono said:

No BBF implementation can work with the Lumix 50/1.4 S simply because to put that lens into MF one has to pull back the ring at the front of the lens barrel.  This deactivates the AF motor. 

Yes, conflict of design philosophies. The cleanest solution would be to allow decoupling of AF from shutter button.

[Chaemono]

Gerade eben schrieb SrMi:

Yes, conflict of design philosophies. The cleanest solution would be to allow decoupling of AF from shutter button.

Yes, but what I’m saying is that the Lumix 50/1.4 S cannot be AFed when in MF by any button (shutter release or otherwise) on neither the SL2 nor the S1/R.  It’s mechanically impossible once the focus ring has been pulled back which is necessary to put that lens into MF to begin with!

[Chaemono]

vor 4 Stunden schrieb chicagophoto:

It also doesn't work with the Panasonic L mount 50mm 1.4 , focusing is only active by the shutter release.

Focusing isn’t active at all by the shutter release in MF mode.  Focusing is active by the shutter release and the joystick (if so assigned) in AF mode.

[SrMi]

25 minutes ago, Chaemono said:

Yes, but what I’m saying is that the Lumix 50/1.4 S cannot be AFed when in MF by any button (shutter release or otherwise) on neither the SL2 nor the S1/R.  It’s mechanically impossible once the focus ring has been pulled back which is necessary to put that lens into MF to begin with!

Your post was clear and insightful. What I meant is that because of physically disabled AF, Leica's approach yo "use MF for back button focusing" does not work. Only decoupling the shutter from focusing (in AFS and AFC) can solve this usability issue with Lumix lenses. I think this the first serious compatibility issue in the L-mount alliance.

[ZHNL]

Thank you everyone, now I see there is no way to have AF not on shutter. I agree a simply disable shutter AF is the best solution.  

Another question: Is there any way I can simulate DOF preview. It seems always focus WO which I like most of time. I haven't run a full test myself but I worried about focus shift with zoom.

I do see my copy of 70-200 f4 is not par-focal, means you can't focus at 200 and pull to 70 or 135 still keep focus, a feature I don't use much but would prefer it has it for video.   

[Guest]

12 hours ago, SrMi said:

Your post was clear and insightful. What I meant is that because of physically disabled AF, Leica's approach yo "use MF for back button focusing" does not work. Only decoupling the shutter from focusing (in AFS and AFC) can solve this usability issue with Lumix lenses. I think this the first serious compatibility issue in the L-mount alliance.

I don’t think you have understood the problem with Lumix lens.

[SrMi]

18 minutes ago, maziatr said:

I don’t think you have understood the problem with Lumix lens.

Which part did I miss?

The only way to use BBF on Leica SL/SL2 is to switch to MF. However, with some Lumix lenses, the only way to switch to MF is to mechanically decouple focusing by moving the focusing ring towards the body (clutch). Therefore, BBF does not work with those kind of lenses on SL/SL2 bodies.

[Guest]

9 hours ago, SrMi said:

Which part did I miss?

The only way to use BBF on Leica SL/SL2 is to switch to MF. However, with some Lumix lenses, the only way to switch to MF is to mechanically decouple focusing by moving the focusing ring towards the body (clutch). Therefore, BBF does not work with those kind of lenses on SL/SL2 bodies.

You are right.  I misread your previous comments and I do agree and apologise