G7 and G85 AutoFocus while shooting video questions

I've been reading about problems with Panasonic G7 Autofocus while shooting video, especially 4k.  Is there a setting for single point AF while shooting 4k video and is it reliable on moving subjects and panning ?

How about the Panasonic G85 ?  Does it have single point AF while shooting 4k video and is it reliable on moving subjects or panning ?

red sled wrote:

I've been reading about problems with Panasonic G7 Autofocus while shooting video, especially 4k. Is there a setting for single point AF while shooting 4k video and is it reliable on moving subjects and panning ?

The AF points can be fully configured, so yes. However, it is not very reliable. Also when you zoom with most lenses, the camera can lose the focus.

My solution is to disable (automatic) continuous focusing during video. The camera only re-focuses when I half-press the shutter button. This works really well for me. Manual focus is also an option. Shooting in 1080 mode instead of 4k should help as well.

For "normal" shooting the AF is not an issue in my experience. However, if you want to shoot sports or birds in flight, then this camera is not for you. That being said, I have shot professional ice hockey without problems (but not next to the rink).

How about the Panasonic G85 ? Does it have single point AF while shooting 4k video and is it reliable on moving subjects or panning ?

G85 is like G7, only better (and it weighs a bit more).

red sled wrote:

OK thank you pannumon for your comments. I appreciate it.

Would the continuous AF be reliable for a bear in a pine tree ? Or a grazing elk or moose ? But not an animal that was walking away from or towards you ?

If you know how the camera operates and you know how to operate it, stationary animals should not be any kind of a problem. In fact I would just make initial focus and lock it there. Animal walking away/towards may or may not be a problem. It depends if you want the animal to be in focus 90% or 99% of the time. I would perhaps use manual focus, because even if the animal would be slightly out of focus for a moment, it would not be so distracting to the spectator.

Would their single-point AF be reliable under these same circumstances ?

I would say that the AF would be usable, but not foolproof. Most of the potential problems can be avoided by extensive testing of the camera, reading the manual and going through every related camera setting. As with stills photography, camera can always be blamed, but at the same time someone more skilled/experienced would probably have been able to eliminate the issue.

P.S. I see I am repeating myself, as I replied to you already in another thread.

Are there cameras in the same price range that could do better with tracking focus for moving subjects during video?

To the original poster: How much of an issue will this moving scenario be for you.  Will subjects moving toward  you or away from you be the primary scenario you will be filming most of the time?  Everything's a trade-off, just be sure your paying for what you really need.

Mark

red sled wrote:

Thank you pannumon. I was almost ready to purchase one of these two cameras but the focus difficulties others were having has given me pause.

I'm not familiar with these AF difficulties as I normally shoot with a Nikon D90 or D300s which I see have phase-detect AF for normal shooting. Perhaps, as you say, it would get better with experience trying different settings.

Are we talking about stills AF or video AF? Because G7 and G85 will be way ahead of any Nikon DSLR when considering video AF. Also the whole "live view" experience should be a totally new world when using a system that is built on top if it.

When it comes to stills singe-point AF (S-AF), Panasonic cameras should focus much faster than you Nikons. Considering continuous AF (C-AF) or tracking focus, expect the Nikon DLSRs to be better (by far).

When shooting video, unless you actively tell the camera where to focus (either by touching the screen or half-pressing the shutter release button), any camera will have difficulties to know where you want the focus to be, or when to refocus. This can be controlled semi-automatically (much like using A or S mode instead of fully automatic mode for stills).

red sled wrote:

Thank you pannumon. I was almost ready to purchase one of these two cameras but the focus difficulties others were having has given me pause.

I'm not familiar with these AF difficulties as I normally shoot with a Nikon D90 or D300s which I see have phase-detect AF for normal shooting. Perhaps, as you say, it would get better with experience trying different settings.

I heard basically the Nikons have useless AF on video...

AFAIK PDAF alone doesn't help in video shooting. Currently there had been a few models having more reliable video AF than Panasonic, e.g., Sony and Canon, are using hybrid AF system (i.e. On Sensor PDAF or Dual Pixel AF), basically are a marriage of traditional PDAF plus Live View. Traditional PDAF of dslr doesn't support live view, and live view been used by video. On video shooting dslr has to lock up the mirror, disable the traditional PDAF module and use CDAF. On pure CDAF operation, Panasonic could be the best until now.

Finally, how serious your video work will determine your requirement on the AF performance. On my GX85 (causal shooting), using the work around solution (MF, disable CAF etc) can satisfy me. Indeed on slow and steady panning, not to zoom the lenses etc CAF is not 100% unacceptable.

If you need the best, I suppose a Sony FF (size, weight and cost) could be a better choice at present (but mnd the 4K overheating). Not very sure but likely not every DPAF Canon supports 4K.

red sled wrote:

alcelc wrote:

red sled wrote:

Thank you pannumon. I was almost ready to purchase one of these two cameras but the focus difficulties others were having has given me pause.

I'm not familiar with these AF difficulties as I normally shoot with a Nikon D90 or D300s which I see have phase-detect AF for normal shooting. Perhaps, as you say, it would get better with experience trying different settings.

I heard basically the Nikons have useless AF on video...

AFAIK PDAF alone doesn't help in video shooting. Currently there had been a few models having more reliable video AF than Panasonic, e.g., Sony and Canon, are using hybrid AF system (i.e. On Sensor PDAF or Dual Pixel AF), basically are a marriage of traditional PDAF plus Live View. Traditional PDAF of dslr doesn't support live view, and live view been used by video. On video shooting dslr has to lock up the mirror, disable the traditional PDAF module and use CDAF. On pure CDAF operation, Panasonic could be the best until now.

Finally, how serious your video work will determine your requirement on the AF performance. On my GX85 (causal shooting), using the work around solution (MF, disable CAF etc) can satisfy me. Indeed on slow and steady panning, not to zoom the lenses etc CAF is not 100% unacceptable.

If you need the best, I suppose a Sony FF (size, weight and cost) could be a better choice at present (but mnd the 4K overheating). Not very sure but likely not every DPAF Canon supports 4K.

Thank you Albert, I appreciate your input. After much thought I believe 4k scenery and 4k time-lapse will be the majority of work for this new purchase. So a wide angle lens should suffice, and moving targets should not be an issue (98% of the time).

No, I'm not looking for the best equipment. I do like the time-lapse options of the G7-G85 models and the 4k video and stills options. So perhaps that opens the door to different, less expensive Panasonics than the G7 (but I would like the best IQ possible in the G7 price range. 4k video and time-lapse video in the camera are the two main considerations.

A recent discussion on G7 and G85  might of your interest.

https://www.dpreview.com/forums/post/62123478

red sled wrote:

pannumon wrote:

red sled wrote:

Thank you pannumon. I was almost ready to purchase one of these two cameras but the focus difficulties others were having has given me pause.

I'm not familiar with these AF difficulties as I normally shoot with a Nikon D90 or D300s which I see have phase-detect AF for normal shooting. Perhaps, as you say, it would get better with experience trying different settings.

Are we talking about stills AF or video AF? Because G7 and G85 will be way ahead of any Nikon DSLR when considering video AF. Also the whole "live view" experience should be a totally new world when using a system that is built on top if it.

When it comes to stills singe-point AF (S-AF), Panasonic cameras should focus much faster than you Nikons. Considering continuous AF (C-AF) or tracking focus, expect the Nikon DLSRs to be better (by far).

When shooting video, unless you actively tell the camera where to focus (either by touching the screen or half-pressing the shutter release button), any camera will have difficulties to know where you want the focus to be, or when to refocus. This can be controlled semi-automatically (much like using A or S mode instead of fully automatic mode for stills).

Thank you pannumon for your patient explanations. Originally I was asking about video AF. I did not realize my Nikons used a different AF for video. Interesting, and that explains why I rarely use them for video as it can be very frustrating because it "hunts" a lot while filming and seems to be out of focus frequently.

After much consideration, I believe the majority of work for this new purchase would be scenery, both 4k video and also time-lapse video in 4k (preferrably) or 1080. Would you still recommend the G7 vs. G85 , or some other model ? I would love a GH4 to grow into but can't swing it at this time. I really do like the Panasonics for flexibility and options for time-lapse in the camera .

The Nikons use CDAF when recording video, not PDAF (they don't have on sensor PDAF like some newer Canon DSLRs). While the Panasonic also use CDAF, their CDAF is much more advanced and when using compatible lenses it will also offers DFD (in AF-S it is just as quick as PDAF), which is even better.

I have a D5000 so I can relate to the frustrating Nikon video experience. My GX85 is a ton better in video AF and video in general. G85 will be even better given it supports DFD 2.0.

As for the two cameras, if budget is not a problem, I would strongly recommend the G85 for video work. The IBIS is a game changer for video and allows you to have stable video without a tripod (G85 has Dual IS 2.0 so even better than my GX85). OIS alone simply can't match. The weather sealed 12-60mm it comes bundled with also gives a nice range and gives you a whole weather sealed package (given G85 is weathersealed, while G7 is not).

If you worry about hunting, you can set the AF so that it only refocuses when you half press the shutter button (just turn off Continous AF setting). AF is very fast when doing this (I use my GX85 this way). AF does slow down when recording 4K though vs 1080p. Continuous AF is going to be slowest.

If you are going to use it unattended and need Continuous AF, set your aperture to a sufficiently deep DOF and it shouldn't really hunt. Set a baseline focus point before pressing record. The main people complaining about continuous video AF are vloggers who may be moving back and forth from the camera a lot and they need reliable AF without having to monitor it.

The G85 does have an AF sensitivity setting that allows you to prevent hunting in AFC mode (p211 in advanced manual).

ftp://ftp.panasonic.com/camera/om/dmc-g85_en_adv_om.pdf

You asked about single point AF in video. I presume you mean where it is set to center or you get to select the point. If so, yes the G85 does support it. It supports every AF mode in video that it does in stills (see p93 for all modes). There is a ton of customization available in video (remember to set the mode dial to the Creative Video Mode p85).

I'm a novice with the G80 and have just got the 100-400mm PL lens so my experience is limited. I have the camera set to AFC and the AF mode set at Custom Multi. A link to a video below using these settings, maybe the Tracking setting in AF mode might be more effective.

https://youtu.be/M2DrTPNK7T4

I've no complaints with this camera or the 100-400mm lens in stills or video. I think the consensus is the newer GX9 and G9 autofocus in video much more effectively. I love the size and handling of the G80, it's a great camera.

Thank you red sled for your kind words. I've had the 100-400 lens for about a week, it's much heavier in weight than I was expecting for a compact lens but then that's what you get with quality glass. My old Canon 500f4 weighed a ton!