GH5 Can anyone test and confirm these improved AF results with GH5?

I tested it with Pana Leica 12-60 and it does work indeed. Even more, it is enough to change the shutter angle to just 179 degree to experience the faster continious autofocus speed. To do so, enable "Synchro Scan" in the 1st menu and then you can change your shutter speed in 1 degree increments. But note that it doesn't improve the speed in 24fps, as the guy who discovered it mentioned.
 
The logic on this makes sense.

Marionathan, to clarify your findings + the video - no shutter speed change at all works for 24fps?
 
This is so weird. For some stuff I suppose I could go with 25p for better AF performance but not ideal. Panasonic should be able to improve on this to get 24p or 23.97 to work. What I was told early on was the higher frame rates like 60p do better because the camera has 3 times more frames to work with for AF. But the difference in 25p vs. 24 is night and day.
 
I'm talking out of my butt here, just thinking out loud as to how 25p is so much better vs 24p. Does it have to do with how 25p is divisible in relation to shutter or something? 1fps can't possibly make a difference physically, so it has to be in the way the signal is processed.

I guess if you need AF for b-roll shots you could shoot in 30p with a faster shutter (179d? or 150d?) and then conform in post for a subtle slow motion effect on the footage. But for live motion stuff, no.

Then again, in the age of web delivery, does 24p vs 25p doesn't really matter, but, if you aren't just shooting a one off and are rather implementing this footage with other footage, projects, or workflows it becomes a big issue.

One more: for select shots, could you shoot 25p and then conform in post to 24p? Wouldn't work for audio sync on longer shots with dialogue, but could work for a lot of things I assume as a temp. fix?
 
If you know that you will not be required to make a true 24P (or 23.97) deliverable, then 25P is a fine frame rate to get a cinematic motion cadence (when coupled with a shutter angle close to 180º.) Every digital outlet I know of supports 25P.

Shooting 25P for 24P isn't impossible, either. Worst case scenario is a few extra steps to ensure audio sync.

What I wonder is, if one is so concerned about a cinematic look that they fret over 24 s 25 fps...why the hell are they using continuous autofocus? :-P
 
This whole thing is crazy. I really would like to hear a Panasonic rep explain this one away. In the mean time, maybe shooting at 30p and editing on a 24p timeline would be the best shot. I use Edius and it will just default to throw the extra frames away when the footage is thrown on the timeline. If the camera will let you film 30p with a 1/50th shutter it should be no different than 24p with a 1/50th shutter. I am also assuming the audio is consistent between 24p, 30p and 60p.
 
I don't have any wide aperture lenses with me at the moment, but so far I've got very good results with a 14-140 and an Olympus 12-40/2.8 zoom. I need to do more testing to be confident, but so far this is very promising. I look forward to read what everyone else says.
 
I tried this again last night and it work very well again. I stood far away from a subject and walked towards them until the face took up all most all of the frame. The face stayed in focus. This was with my F/2.8 zoom. For now maybe I'll shoot 25p with a 179 degree shutter. Maybe.

So the next question is, does this work the same with the GH5s?
 
According to this video it seems like there's possibly just a "bug" with having your GH5 on shutter angle (ANGLE/ISO) instead of shutter speed (SEC/ISO).
Skip to 7:28 to see the actual testing: https://youtu.be/Qt4DQeQFvQk?t=7m28s

So in 30p, 1/60 is actually the "fast/better" AF, but for some reason in shutter angle mode, 180 degree results in a slow/worse AF. 180 degrees should be 1/60 though, but it isn't. Setting your camera to 179 degrees or lower will result in the faster AF.

I have an idea of why this might be the case though.
"30p" is actually 29.97fps, which means a shutter angle of 180 would actually be 1/59.94. When you have it on the shutter speed mode (SEC/ISO), you're inputting in 1/60, which is greater than 1/59.94 which is why you're getting that "fast" AF.
This is also the reason why even setting it to 179 shutter angle (which is 1/60.27) works, because it would be greater than 1/59.94.

Now you ask, what's going on in 25p (which is 25fps) then? I have no idea. That was just my shot in the dark for why this might be the case, but someone more technical can chime in.

The conclusion though seems to be that if you were shooting in "shutter speed" mode (like I was), this doesn't change anything about the AF performance of your GH5 if you were shooting in standard settings. But if you were shooting in the "shutter angle" mode, now you know that your AF performance was suffering and you should change it to 179 instead of 180!
 
CSFilms said:
According to this video it seems like there's possibly just a "bug" with having your GH5 on shutter angle (ANGLE/ISO) instead of shutter speed (SEC/ISO).
Skip to 7:28 to see the actual testing: https://youtu.be/Qt4DQeQFvQk?t=7m28s

So in 30p, 1/60 is actually the "fast/better" AF, but for some reason in shutter angle mode, 180 degree results in a slow/worse AF. 180 degrees should be 1/60 though, but it isn't. Setting your camera to 179 degrees or lower will result in the faster AF.

I have an idea of why this might be the case though.
"30p" is actually 29.97fps, which means a shutter angle of 180 would actually be 1/59.94. When you have it on the shutter speed mode (SEC/ISO), you're inputting in 1/60, which is greater than 1/59.94 which is why you're getting that "fast" AF.
This is also the reason why even setting it to 179 shutter angle (which is 1/60.27) works, because it would be greater than 1/59.94.

Now you ask, what's going on in 25p (which is 25fps) then? I have no idea. That was just my shot in the dark for why this might be the case, but someone more technical can chime in.

The conclusion though seems to be that if you were shooting in "shutter speed" mode (like I was), this doesn't change anything about the AF performance of your GH5 if you were shooting in standard settings. But if you were shooting in the "shutter angle" mode, now you know that your AF performance was suffering and you should change it to 179 instead of 180!
Click to expand...

I think the "bug" is there is some hidden step that takes up time. So if your shutter angle or shutter speed is equal to 1/2 the time of the cycle, with that extra hidden time, there is no time left to perform AF again during the cycle. the shutter speed must be faster (take LESS time) than the time for 1/2 a cycle. Then it can be performed again in the 2nd half of the cycle.

Am I wrong thinking that in 30p, 1/60 is you get the slower/bad AF not the "fast/better" AF? I was under the impression it does not matter if shutter speed or shutter angle is used. I could be wrong, so if I am can someone correct this?
 
This makes no difference when shooting in 4K 60p with a native 15mm. I seem to get best AF performance on my GH5 at 1/60th shutter speed in 60p, but as has been shown since the beginning, GH5 AF performance is unreliable and completely inconsistent regardless of shutter speed or angle in 60p. The thing just will not ever do the same thing twice with the same scene.

Cheers, Pete
 
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