Wtf is that?! GH2 sensor output...

just looks noisy to me, what iso setting were you using? this is straight from the camera?
 
When asking for help please provide every technical information you can.

Recording format, ISO, shutter, SD card, etc.

It is known that Extender makes noise more visible.
 
also include what player you are using. Some are known to have artifacts playing AVCHD.
 
Well, brand new GH2 fw1.0 PAL, I was playing with settings so can't recall
them for sure, however if I clearly remember all was set to default, except:
(M) manual shutter 1/50, apert. 5.6
Cinema profile
1600iso
720p, SH
WB "clouds"
EX. TELE CONV
sRGB color space
Recorded on SanDisk 4GB Extreme III SDHC card (the only one I had at the moment). Player does not matter as you can download .mts which is untouched file, straight out of the camera. What's worrying me is that there is strange, pulsing, kinda "pumping" noise that cycles trough the footage in a fixed intervals (some less than 1 second). I would NEVER expect that, nor I've seen it so far anywhere...
 
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Welcome to extended tele mode! Not to mention you're using it at ISO 1600 with 720p - that's not a great combination if you want decent footage! I really wouldn't use the tele mode above ISO320 unless you want spurious noise that's hard to get rid of and which hurts compressibility.

The "pumping" I've also come across in ex. tele mode but with a blue colour cast from using it under halogen lighting. The way I get rid of it is to use temporal smoothing in Avisynth (spatial not required), which cleans it up very nicely.

I think the solution here is simply not to shoot in extended tele mode with such a high ISO - especially in 720p mode. The settings you chose to shoot that footage with wouldn't really be optimal for most camcorders available, let alone the GH2!
If you consider that it's effectively sampling a small portion of the sensor - rather than downsampling the full image from the entire sensor - you can expect the noise profile to be coarser and "grainier". It's like taking one of those small-sensor HD cameras like the Kodak Zi8 and making it shoot in low light: the results are pretty dire.

Hope that helps.
 
JamesRitson said:
you can expect the noise profile to be coarser and "grainier"
Click to expand...

Thank you James. I know that, but I was using highest iso just to test my newly bought camera. This cycling "pump" issue is really bad and frightened me up. So you say it is normal..? Not to worry about? One of the reason I bought GH2 is Tele-Ext-Con. mode...
PS
I forgot to mention that I was using CPL filter from Marumi - does it make any impact on the pumping issue?
 
Think of it this way, when shooting 720p ETC, you are effectively using a single-chip 1/3" format camera, and iso1600 is approximately equivalent to what would be 12db gain in most 1/3" cameras. Also, being at anything but "daylight" WB will also increase your noise. "clouds" WB is essentially adding even more gain to your red channel. It also does not help that most of your detail is underexposed.
 
All right, but is it typical that this noise pulses that way? Its like a heartbeat, up and down, up and down - never seen it before on any camera. Even 1/3''.
 
.....I was going to say....I see no pumping whatsoever in your clip.... just a whole lot of noise.
 
Glad to be of service. :)

But don't worry...we've all been there before...playing our clips in one player and freaking out over the IQ (mine was on VLC player with its crazy bugs) and then finding it plays just fine in another player. Being that it's a new camera...I don't blame you at all.
 
Guys - many thanks for your attention, finally my problem solved! First of all - newest VLC plays it badly, causing pulsation. There was also a misconfiguration of my graphic card too (shame on me), so the other players could not play it correctly as well... You were looking at a source file that was correct, but my pc wasn't, so you did not know what I've been talking about... I have spent whole night on reinstalling and configuring my computer and to be short: now the same footage plays as expected (except of VLC), even on Windows Media Player it goes smoothly. Just dark and noisy, because of such settings on a camera, but pulsation is gone (as it never existed :))

Oh men, I wouldn't resolve it without you. I was already sending back my brand new GH2 to the service center... Thank you all once again, Waldi.
 
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