GH4 Best way to handle AF for moving subjects with GH4?

Is your question for photos/stills or for video? The Camera Store has a couple of videos that you should watch: one focused on videos and one focused on AF for stills with moving subjects. For videos, the GH4 does AF slowly as best it can for smooth videos. For stills, the GH4 seems to be close to the speed of very expensive FF cameras... Al
 
http://www.43rumors.com/page/3/

"Today TheCameraStoreTV team posted this autofocus shootout video to see how close the latest generation mirrorless camera are compared to the king of sports photography, the $6,500 Nikon D4s. Chris tested the Fuji X-T1, Sony A6000, Olympus E-M1 and Panasonic GH4. Well according to their tests the Panasonic GH4 autofocus performance is damn close to the Nikon which is a huge surprise in face of the massive price difference. Yes, the day will come when a Mirrorless camera (maybe a GH5?) will match the best DSLR autofocus."

First test was continuous AF at max. re-focusing burst speed (7.5/sec in the GH4, I believe); then AF-S/burst.

Uwe, are you evaluating the GH4 for DPRev now?

Peter
 
Unless you shoot video for a documentary where flaws like searching for focus and/or shortly setting it on the wrong object can be forgiven - best focussing system will be a good camera assistant.
 
a well lit subject and 14-140 lens =) it always surprises me how well it auto track focuses, it rarely if ever hunts. i shoot in spot/box focus (whatever you call it, the one with the adjustable box size) mode and when i have the luxury of a tripod i just track with my finger on the screen. its not perfect but has worked well for me so far.
 
go as wide as possible the wider the lens the less the autoocus has to wok to hunt.

Seriously shooting at 14mm or 12mm makes focusing much easier either auto or manual.
 
My experience shooting 4K using AFS (haven't bothered with AFC) is it really sucks. Much more than GH2/GH3. This could be because 4K is using more processing power and the frame rate is 24fps. Thats the bad news. The good news is MF has assist and like the BMPCC it's been the only reliable solution I've found for documentary.
 
I mean for video, stills are no problem for my style of shots. Right now I try to use AFS in video by half pressing the shutter and then rolling the video. If things move I am lost for people or animals moving out of focus. Maybe using AFC with a larger focus point could help a bit?
 
ustein said:
I mean for video, stills are no problem for my style of shots. Right now I try to use AFS in video by half pressing the shutter and then rolling the video. If things move I am lost for people or animals moving out of focus. Maybe using AFC with a larger focus point could help a bit?
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Which lens are you using and at what focal length? What is the lighting like where you are shooting? All of these can factor in to the autofocus. Some lenses like the 20mm are pretty slow at autofocus and hunt a lot. Other lenses like the 14-140 autofocus very fast. The darker the environment the harder the system has to work to find focus. The wide you go the easier it is for the system to autofocus.

Autofucus on the GH3/GH4 is pretty darn impressive for video but is far from perfect like on a traditional video camera. Welcome to the world of DSLR focusing. When the environment gets complex you really need to switch to manual focus so the camera doesn't hunt a lot. You may have to invest in tools like a loupe or an external LCD monitor. Have you tried the focus peaking on the GH4? I'm jealous since I don't have focus peaking on my GH3. I have to use other tools like a loupe to handle manual focusing. The focus peaking should help you a lot.
 
Uwe,

It's good to see you on these forums.

AKAIK the AFC on the GH3 was intended for stills, & not video, so likely the same on the GH4.

For constant autofocus I believe you still need to enable "Continuous AF" on page #2 of the Motion Picture menu.

Been meaning to properly test this functionality so please share your results.

Best,
Bern
 
ralfmouth said:
Maybe I don't know how to use it but I now turn off focus peaking. It feels better to see what's in focus instead of relying on a mask of blue dots.
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Different folks will have different perceptions on this. On the GX7 I turned peaking off, I felt it "got in the way" of seeing focus. I tend to use the MF+ASSIST a lot more. On the GH4 I find it actually helps hit focus a bit quicker, but I may still turn it off as I get used to the camera.

ralfmouth said:
I will say it's a really good indicator of DOF though.
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Perhaps only to a limited extent. DOF is defined as the "zone of acceptable sharpness" and it has no sharply delineated near and far limits. No "sharp" transition. If you have CONSTANT PREVUE set to ON you not only see the exposure effect of aperture with the EVF or LCD in Manual still or video modes, but also may be able to see the "zone of acceptable sharpness" unless you are at a wide angle focal length.
 
No defined "sharp delineation" - that's probably really why I haven't been using it. The sharp "zone" can be broad for pinpoint focus. Then again, I've been using it with wide angle long shots mostly, and it occurs to me from what you said that peaking might be better used in shallow DOF cases (where the zone is more defined).
 
I was a little nervous of the C-AF (Creative Movie Mode) for my use underwater, as I have no way of MF using the focus ring or using the touch screen.

I have to be honest, running it a f5.6 and AF-C has been amazing in the short time I've used it. I can't see any visible hunting in my shots. Very impressed.
 
ustein said:
I mean for video, stills are no problem for my style of shots. Right now I try to use AFS in video by half pressing the shutter and then rolling the video. If things move I am lost for people or animals moving out of focus. Maybe using AFC with a larger focus point could help a bit?
Click to expand...

Have you tried the lock-on "tracking" mode setting in the Fn3 button focus mode choices - pg 96 in the"complete" GH4 manual? I've used it several timers with mixed results in the GH3 (GH4 not yet here). It's supposedly active in video recording.

Peter
 
TheTrickster said:
I was a little nervous of the C-AF (Creative Movie Mode) for my use underwater, as I have no way of MF using the focus ring or using the touch screen.

I have to be honest, running it a f5.6 and AF-C has been amazing in the short time I've used it. I can't see any visible hunting in my shots. Very impressed.
Click to expand...

This is what I do as well. Run with the Lumix 14mm on a glidecam in AFC at shutter f/5.6 and focus area set to 49 Area. I'm also thinking about getting a brushless gimbal and using the Panasonic WiFi app for rack focus.
 
I've been having issues with this as well. I find that with an Olympus 17mm it takes forever to change focus even with tracking. In most of my shots on a stabilizer with moving subjects, it stays focused on the background no matter how close and how much area of the image the subject takes up.

Curious if the Panasonic lenses are better at this than third party lenses?

Cheers,
pete
 
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