GH5 Native Panasonic Lens and Autofocus Conflicting Behavior

[Hugh DiMauro]

I use my GH5 cameras strictly for video. I have disabled my record button because it's too small and finicky whereas the main shutter button is larger and easier to acquire when ready to start shooting video. I own the following two lenses:

1) Panasonic Lumix 20mm G 1.7 Aspherical prime lens
2) Panasonic Lumix 14-140 G Vario 3.5/5.6 Aspherical zoom

Autofocus does not work the same for each lens. Is this normal?

*When using the 20 mm prime lens, "quick autofocus" works very well (constantly acquiring focus while not actually shooting video) but it won't allow me to to use my AFF/AFS menu setting. When I turn on my GH5, I immediately get a message instructing me to "Switch to AFS." Even when I ignore it and keep my switch at AFC, "AFS" appears next to the single area focus icon on the top right of my viewfinder. Is this normal for this lens?

*When using my Lumix 14-140 lens, "quick autofocus" will not work and in order to make the autofocus work at all I must actually shoot video to acquire focus. HOWEVER, this lens does allow the use of my AFF/AFS menu settings. According to David Thorpe's "GH5 Menu System Simplified" book, he says "...use AFS by half pressing the shutter button to acquire locked focus when your subject remains absolutely still and use AFF while half pressing the shutter button if your subject is fidgety and moves around a lot as AFF will constantly acquire focus on a moving subject. When shooting video, move the switch to AFC." However, I notice half pressing my shutter button in AFS/AFF mode with this lens will not acquire focus in creative video mode. Does the AFF/AFS shutter button-half-press-to-acquire-focus NOT work in creative video mode and only in photo mode as described in Mr. Thoorpe's book?

My question is: Do varying native, Panasonic M43 lenses display different menu use characteristics?

Thanks for your help.

 

[Bruce Foreman]

The Lumix 20mm f1.7 lens does not work with AFC on any of Panasonic's bodies. You have to be in AFS or MF with this lens.

Just the same, I like this lens, some feel it is slow to autofocus but I've never been in that much of a hurry anyway. And if I have any problem with focus "hunting" (low light can be a problem) I simply go to MF.

 

[Hugh DiMauro]

The Lumix 20mm f1.7 lens does not work with AFC on any of Panasonic's bodies. You have to be in AFS or MF with this lens.

Just the same, I like this lens, some feel it is slow to autofocus but I've never been in that much of a hurry anyway. And if I have any problem with focus "hunting" (low light can be a problem) I simply go to MF.

Thanks for taking the time to reply. Believe it or not, with all of the GH5 autofocus complaints, I must say the autofocus works quite well with the 20 mm lens. In my experience, its been a fabulous lens.

 

[Peter Berry]

I've found the GH5 "quick AF" setting to be unreliable in video & stills - even with the videocentric 12-35 and 35-100 2.8's. You don't get any AF confirmation, as in the AF-S single area box outline turning green. Try setting quick AF to off, use a 1-area focus box of appropriate size, and set switch to AF-C. This will still allow initial AF-S w/ half-press confirmed with the green box before shooting, and when shooting allow the AF-C to refocus as you re-frame. Works with matrix also, but it will pick the highest contrast area for re-focus - poss. not your intended area...