View Full Version : GH4 Doesn't Auto-Focus Worth #$@!


Dave Allen
June 28th, 2015, 03:00 PM
Picked up a GH4 and the Oly 60mm macro lens. Set it to 4K at 30 fps, then tried 24 fps, then 1080. Set it as AF/AE Lock is set to AELOCK, AF/AE LOCK set to off, shutter AF on, and QUICK AF on.

Tried both AFS/AFF and AFC switch settings. The camera doesn't autofocus worth @#$!. It's running body firmware v 1.1, and the lens firmware 1.0 with the latest body firmware on its way.

When I slow pan on macro, it sometimes autofocuses after awhile, other times it WAY overshoots the focus to a blurry mess, other times it overshoots, then undershoots and generally hunts all over the place rendering it useless.

Now I know nobody is complaining much using wide lenses and autofocus, but I am still trying to figure out of the camera is junk when it comes to macro autofocus, or is the operator junk? Panasonic support line is a joke. They advise you that calls are monitored and recorded, then when I told them I do the same, they said I don't have their permission to which I laughed. I'll be sure to share that with the Panny guys at NAB.

I am about ready to dump it all for the Sony A7RII if I can't get it to autofocus decent.

Noa Put
June 29th, 2015, 07:20 AM
Now I know nobody is complaining much using wide lenses and autofocus, but I am still trying to figure out of the camera is junk when it comes to macro autofocus, or is the operator junk?

I only use autofcous by pressing the shutter button to focus and then release the button so it locks the focus and all my shots are in focus and if the camera is not able to do so I switch to manual and focus myself.

You can't expect a dslr with a macro lens to do 100% accurate autofocus while you are panning, either learn to operate your focus manually or buy a small sensor camera that has a much deeper dof. The GH4 is not "junk", it needs an operator with experience to get the most from it.

There are a few camera's though that might work better for you, I believe the canon 70d has a very good autofocus system and I have seen some impressive autofocussing on the sony a6000 and eventhough they are better don't expect them to be failsafe.

Noa Put
June 29th, 2015, 07:26 AM
Panasonic support line is a joke. They advise you that calls are monitored and recorded, then when I told them I do the same, they said I don't have their permission to which I laughed. I'll be sure to share that with the Panny guys at NAB.

So their support is junk because they monitor your calls or their support is junk because they didn't support you in any way? Calls get monitored often but as far as I know that is to improve their service, my wife has worked in a callcenter of a large telecom business and every call she had with clients was monitored, they used those calls to judge her performance so essentially it was a constant training they got which was only beneficial to the client.

Robert Benda
June 29th, 2015, 09:27 AM
You're right, Noa. Calls do get monitored mostly to keep tabs on the employees, though it does help in the case of a really awful (violent) customer calling. I did work for Amazon.com and it happens.

The 70D is the king bee when it comes to autofocus, and focus tracking. You need to use STM lenses for the absolute best results, which aren't the best quality in the world, though I haven't gone really high end like L or Cine lenses. Maybe I'll rent some someday.

I'd be curious to know if anyone uses auto focusing with macro work. Even on my 70D I don't use motion/panning when doing real macro work. I manually focus.

Noa Put
June 29th, 2015, 09:39 AM
Calls do get monitored mostly to keep tabs on the employees, though it does help in the case of a really awful (violent) customer calling. I did work for Amazon.com and it happens.

You should have heard the stories my wife told me about not so friendly clients :)

I'd be curious to know if anyone uses auto focusing with macro work
Macro shots require manual focusing, focusing is very critical and you can't expect that your camera can guess it right, I have a canon macro lens that I used on my 550d and it certainly required very precise focus adjustments.

Gary Huff
June 29th, 2015, 10:06 AM
I'll be sure to share that with the Panny guys at NAB.

Oh, so you're one of those people.

Dave Allen
June 29th, 2015, 03:02 PM
Noa, the issue is they want to record conversations, and thus have no expectation of privacy, but they demand you not record the same recorded call. I realize some prefer to argue via straw arguments, but I save that form of entertainment for the political forums. I am here to rely upon people with far greater expertise than I on some new gear unfamiliar to me at this point.

As to macro, it's not possible in the environment I shoot in to use manual focus. The subject and conditions are too dynamic, the depth of field is too limited and I have middle aged eyes.

With my old 3ccd HDV cam, I could zoom in with +3 or + 5 achromatic diopters on the fixed zoom lens till either autofocus went out of focus, then I pulled back a bit, or till the subject was framed and sized right. At those points, focus was rarely lost as the tiny subject moved about a bit.

I am sure the GH4 and Oly 60mm macro works great on a tripod shooting stills when you have time to compose, and focus, and focus peaking works for stills, but it is my understanding focus peaking does not work in 4K video mode on the GH4.

I hear the camera autofocuses well with the wide zooms, but macro is my thing.

Unless I am off on my cam settings, perhaps either a zoom with image stabilization and with achromatic diopters might be better, but not as good as needed. That's why I wonder if the new Sony A7RII with advanced autofocus might be better suited for my digital video shooting style.

William Hohauser
June 29th, 2015, 04:20 PM
If I am reading your description of your old HDV camera correctly, you were not using macro but zoom extenders. Macro is frequently enabled by changing the back-focus of lenses which AF has a hard time dealing with, of course depending the AF technique used by the camera and the subjects being photographed. Auto focus with zoom extenders can work better.

The reviews I have seen have noted that this particular lens is not the fastest macro AF lens around especially with subject movement. Personally I have not found any auto-focus lenses that were reliable at all with macro. Manual was the only way to go. The GH4 however, with the right lenses, has very fast auto-focus in most typical photography situations.

Your photo needs are specialized and I hope you can find the right combination to continue to film the way you want.

Dave Allen
June 29th, 2015, 04:54 PM
Thanks William and others. I was using a screw on achromatic diopters on the old HDV cam and it worked quite well. I never saw the need for a dedicated macro lens. With the same cam, I could screw on a wide angle adapter and that worked really well too. Now I am faced with buying dedicated fixed and zoom lenses.

With the Sony FS700 I only needed 4 lenses, an ultra-wide zoom, and low light beast, and a longer zoom, but that's all tripod work on more or less fixed larger subjects.

For travel, the form factor of video cams just does not work as well as the new crop of dslr's that are now doing 4k/quadHD internal at less than half the size and weight. I just need to solve the macro focusing issue if that is even possible.

I wonder if I go to a Panasonic zoom with an achromatic diopter added on the front if that would autofocus better for video than the dedicated macro lens. With the former, at least with the right zoom lens choice I would get image stabilization.

Bryce Comer
June 29th, 2015, 06:53 PM
Hey Dave,
For sure the focus peaking works, & works very well in 4K movie mode.
As for keeping things in focus in video mode using AF, well i'm just not sure that the GH4 will be your friend in this situation. I would definitely try using manual focus with focus peaking, you may find it easier than you think to keep things in focus with it.

Dave Allen
June 30th, 2015, 08:36 AM
I don't think peaking works in autofocus mode.

Noa Put
June 30th, 2015, 08:42 AM
Why would you need focus peaking in automode? Focus peaking is a visual aid when you are focusing manually.

Pete Carney
June 30th, 2015, 08:44 AM
My testing with a 17mm Oly lens in 4k on a stabilizer is that the cam wants to back focus on the background even when the subject fills more than 2/3rds of the frame when it is moving with you. I have never found a way to make it want to stay up front on the subject.

After a number of tries, I have given up auto focus for anything. A half press of the shutter button locks focus extremely well, but then at some random point it always starts hunting around for the background. Manual focus is the only way to truly get the GH4 to stay put that I've found.

If someone has a solution they can spell out of exact settings to get AF to lock with a half press then not change while recording I'd love to hear it.

Cheers,
Pete

Vishal Jadhav
June 30th, 2015, 12:38 PM
When i use a autofocus lens panasonic 12-35 f2.8 on the GH4 , it focuses auto on the C1 and C2 mode however on the C3 modes the autofocus stops of and i don't have any idea about why it does it.
The peaking allows me to do the focus fast however i would love the auto focus to work on the C3 modes, anyone else faces this issue.

Noa Put
June 30th, 2015, 01:45 PM
If someone has a solution they can spell out of exact settings to get AF to lock with a half press then not change while recording I'd love to hear it.


It must be a menu setting that is causing this because I always press the shutter halfway to set focus and it remains in manual focus untill I half press the shutter button again during recording to refocus, I have the switch on the back of the camera set to afs/aff and I have continuous auto focus set to off in the menu.

Dave Allen
June 30th, 2015, 07:01 PM
Noa, the reason for wanting peaking when using autofocus while filming is it is usually far easier to see in an extremely dynamic environment with middle aged eyes the dazzle of the focus peaking to confirm the autofocus is right than it is to visually see that the moving tiny subject looks in focus.

In a dynamic environment with the moving subjects ranging in size from of a large goliath beetle to a subject as small as the size of these letters in this sentence, and with the accompanying shallow depth of field at such high magnifications and with no time to set up a tripod, manual focus is rarely realistic and handheld is used. I know, all those things conspire against me, but with my old bulky 3CCD HDV cam, I regularly nailed it, with footage usable 90% of the time, but HDV is a dinosaur now. 4k footage acquisition offers opportunities in post for stabilization, digital zooms, reframing and slow digital pans.

Jim Michael
June 30th, 2015, 08:30 PM
So now you have a smaller circle of confusion and shallower depth of field. Very challenging. Can you push the diffraction envelope a little and crank up the light with a smaller f-stop? What does Online Depth of Field Calculator (http://www.dofmaster.com/dofjs.html) say your focus depth is at your current aperture? How does it compare with your old system?

Noa Put
July 1st, 2015, 12:37 AM
Noa, the reason for wanting peaking when using autofocus while filming is it is usually far easier to see in an extremely dynamic environment with middle aged eyes the dazzle of the focus peaking to confirm the autofocus is right than it is to visually see that the moving tiny subject looks in focus.

Your best bet might be teh sony a6000 or the canon 70d with the macro lens if you don't want to break the bank because I have seen very good results from their autofocus capabilities, but if your requiremet is 4K I don't know what camera would be able to do what you expect from it.

Dave Allen
July 1st, 2015, 03:27 PM
Noa, that is why I am thinking of the new Sony A7RII, as it has 399 focus points on it sensor.

Noa Put
July 1st, 2015, 04:33 PM
Those 399 focus points are most likely used to take an image but I"m sure that will not apply for continuous autofocus while shooting video.

Dave Allen
July 1st, 2015, 08:18 PM
Sony does have a promo film out that seems to really promote the continuous autofocus capabilities of the new cam.

http://www.youtube.com/watch?v=5Ea5lKyWxGc#t=42

Ade Towell
July 2nd, 2015, 09:43 AM
samsung nx1 is 4k and apparently has very good af