@Elenion:"I think it is quite incredible that no one here can see the effect ..... just take a medium-wide lens, go outside in the garden..."

OK, I did just that. I strapped an HMC40 onto the tripod along with my GH2, and went outside in the garden. What I see from both cameras is simply what I would expect to see from 24P from any camera. But judge for yourself:

For what it's worth, we haven't had this problem on our GH2 any more then we do on our non MX'd RED. Progressive cameras create this effect, and the sharper the image, the worse it gets, or so had been our experience.

Have people done an AVCHD vs MJPEG at 1080 comparison with this?

Hi there, one of the samples posted from above is from me (Gunther). Regarding strobing, while I haven't noticed anything wrong with the 1080p24 mode from GH2 (also compared to GH13) as can be seen in my comparison video above, what I have noticed is something strange: I always use the main trigger (release button) to start filming (the one used for photos normally). When I use the dedicated video button, the GH2 seems to switch and use the automatic 1080i50 mode (I have a PAL model). Could this be one of the main reasons for the observed problems, i.e. people not using the main trigger in creative movie mode and then getting shutter speeds, etc. messed up?

@Bezerk
don't you think that the strobe is evident even in a simple scene like this?

Watching the vids above, I have downloaded the middle (fastest / worst) one and stepped through it in VLC and can't see frame-by-frame what's wrong. But the fast motion does look a bit unpleasant and it reminded me of something I've seen recently, connected with motion and dark / light transitions.

On a shoot I did that there is a REALLY strange effect where there's a "persistence" to black objects which looks odd - this video shows you an upload of part of the offending shot (otherwise untouched and only shortened and transcoded to mp4 for Vimeo as the original is 5 mins long). Recorded originally in 1080 50i but I'm wondering if there's some weird GH2 processing thing going on and that it's related to strobing in some way? Never seen this in my other cameras:

@bdegazio Have a look at the funny three-sided hole above the strings (it's the same shape as the one bottom of frame), as the hand crosses it from time to time during the clip. Do you see it apparently sitting "on top of" the hand as it sweeps past? If not maybe it's my monitor! That might explain why some of us are seeing these things and some aren't.

@Mark_the_Harp

Downloaded the mp4 file, single-stepped though it and it looks OK. Just the normal superimposition you would expect from a certain amount of motion blur. The effect must be in your monitor, or maybe it's a perceptual thing like those "figure/ground" reversal tricks.

@Mark_the_Harp
As a result of the various tests and discussion in this thread, I've come to the conclusion that the strobing is a combination of:

1) common 24 fps strobing
2) irregular decoding in playback (i.e sometime a frame is decoded a field or two late)
3) interference in playback with 60 fps monitors
4) possibly some exaggeration due to highly detailed GH2 image or absence of motion-blur

@bdegazio: "2) irregular decoding in playback (i.e sometime a frame is decoded a field or two late) 3) interference in playback with 60 fps monitors"

I agree about these kinds of playback issues; I find my footage looks different on my various different computer systems, but once I finally edit it to an HD clip for playback on a widescreen TV via a TViX, it becomes consistent and OK. One test I did for myself - and the one that convinced me that my raw GH2 footage was OK - was to transcode the .mts file to a format with intraframe compression (e.g. Cineform) and add manual 3:2 pulldown as I did so. My computer systems all play 24P packaged within a pure 60P intraframe footage very consistently.

@bezerk55 There is nothing different about your 3 videos that I don't already see in every other HD video on the Web from any camera. If anything what I see is "tearing"...which I've already mentioned is a sort of pet peeve of mine with ALL HD videos I've come accross (No matter how cheap or expensive the camera). The faster the pan...the easier it tears. This is not GH-2 specific.

With that said...I challenge any of you making these "strobing" claims to post footage like bezerk55's with a camera YOU think doesn't display ....um....strobing.

Oh...@CobyD thanks for your footage. I see no difference in it either.

@ian_t

don't know if you have explored this tearing problem on your computer much, but if it is the type of tearing i am familiar with, it could very well be a problem of your video renderer not vsyncing properly or at all. on windows xp there are many video renderers depending on your video card capabilities and drivers, from the standard "video renderer" to "video overlay", VMR7 and VMR9. All have varying ability to vsync properly. On Vista and Win7, EVR renderer generally solves the vsync problem. the best way to find out would be to play with media player classic home cinema which gives you access to many different renderers including evr and evr sync and d3d9 fullscreen with many different vsync options. most importantly it has a "tearing test" to show vsync problems (it draws a red line travelling across the video to see if it doesn't line up properly).

another very useful tool in mpc-hc that everyone here should probably check out before blaming the gh2 is the playback graph which shows you in real-time graph form the timing difference between what the video decoder requests of the frame timing, vs what is actually displayed on screen (jitter). See here for example of detailed statistics: http://imageshack.us/photo/my-images/827/capturestat.jpg/

The type of strange strobing I've noticed on my GH2 is due to sharpening, when you're viewing on LCD monitors.

The LCD monitor issue hasn't been mentioned, and isn't widely understood - LCD pixels respond slowly, much slower than the specs lead you to believe. To get the faster response times, they are optimised for low-contrast transitions. The worst-case scenario for an LCD pixel is having to switch from black to white (or the other way). So when a lot of pixels have to change contrast quickly, LCDs do a really nasty pixel-level flickering that you wouldn't see on another display technology (even old CRTs).

The worst example is a 1:1 black and white checkerboard pattern like this: http://protie.sweb.cz/checkerboard_1920_1080.gif . Be sure to view it at 100% without any scaling - now scroll the image slowly in your browser. LCD screens will flicker like crazy (but some screens are worse than others).

(@Vitaliy_Kiselev, links break when they end in a full stop. http://protie.sweb.cz/checkerboard_1920_1080.gif. doesn't work http://protie.sweb.cz/checkerboard_1920_1080.gif . does (space between URL and full stop)).

What that means for footage is that any moving high contrast edges, and especially where there is a lot of small contrast detail like grass, tree branches etc, will flicker on an LCD screen - but it's the screen causing it, not the footage. I see this effect quite clearly in the last video @Ian_T posted, in the earlier tree shots (especially around the grass blades), and I've seen it on my own 24p GH2 footage.

That's partly why I'd like a hack that can disable sharpening altogether, -2 isn't fully disabled. It would also give a more smooth cinematic image and allow better post sharpening.