Just as a point of interest for those who are comparing bit rates, We deliver finished HD masters to the broadcast networks in mxf files at a MAXIMUM bit rate of 50mb/s 50i. The GH4 bit rates seem to me to be a good compromise between quality and efficiency.

I do post production work on a lot of Sony XDCAM HD originated footage which is long GOP 50mb/s and it looks ok. The GH4 will do 200 mb/s in HD. I think we may see some incredible work once this camera is in the hands of talented creative people. I have seen amazing quality shot on hacked GH2 and GH3 cameras. I have also been grading Canon log footage from C300 and C100 cameras and getting very bad results! Why? Because the camera operator was sloppy and did not set up the camera to deliver well exposed and proper white balanced footage. The quality is in our skill, not in the equipment.

@Aria @Vitaliy_Kiselev Defenetly agree. the thing is that I believe that the work Vitaliy have been doing with the GH1, GH2 and the rest of the Hackable Lumix cameras must have had some impact on the rout Pany has taken. Showing the way to the more advanced users and to the pros with his hacks and the big interest they have got from many pros and others (me);) Thanks Vitaly!

comparing the moire from 18sec to 20sec (Red scarlet 4k)

to the GH4 4k 43sec (stairs)

which one would look better?

From what I'm gleaning from the specs posted so far, it's just 8 bit 4:2:0 to an SD card, but you have to use HDMI or the optional A/V brick to get 10 bit 4:2:2. If you select 10 bit output it seems from the "gotchas" in the released specs. like it won't record to the card at all, it just sends video out via HDMI and the SDI outs on the brick.

Another question I have is whether the time code generated is within professional SMPTE parameters so you could master/slave genlock a SMPTE time code audio recorder to the GH4. I don't want to be forced into buying their optional monstrosity in order to sync audio. Besides, it's only 16 bit PCM and God knows how noisy the GH4's audio pre-amps will be.

@LongJohnSilver I find the artifacts unsettling in the Temple and on the wings of the parrot, just have to wait and see how bad they are, but they didn't appear from nowhere.

@TrackZillas I'm not sure on Atomos Blade specs, but it'd be a shame if it couldn't handle 10Bit. From what I've read on the forums about the Odyssey 7Q is that it's an all-in-one beast (reference monitor for both A/V, SSD recorder, multiple signal processor, etc) but it's also fairly new, so CD is slowly releasing updates to increase it's usefulness in the field. Also keep in mind that the SSD's have to be from Convergent Design (to keep up with the bandwidth requirements) as well as the user having to pay separately for codecs. It's not cheap when you add it all up, but it's probably the most compact and practical.

Some of the comments here remind me of those on Nikon forums when the D3 was announced ... and there were horrified people that it was ONLY a 12 megapixel camera. Obviously it was an over-priced useless piece of junk before it was released ... what COULD Nikon have been thinking? Who in the world would ever pay $6000 for an only 12mp camera? Absurd!

But those weren't any other camera's 12 megapixels ... the images were awesome past 3200 ISO (astounding then at that quality) and kept hue purity clear to 3200. I've shot several available-light portrait sessions with it over the years at 3200 ... and gone to 30" prints from it, beautiful things. 50" prints at lower ISO's. Remember, I used 6x7cm roll-film for 20+ years, I do expect a lot from a print.

So ... yea, some of the GH4 specs aren't exactly what all of us would prefer ... but darn it if I don't think I'd be able to shoot some good and very usable footage with this cam as spec'd. If the mechanical/internal software hold up to hopes, it's going to be a useful tool. And a big step up from the GH3 and other similar cams.

Now ... to start getting enough more paid gigs of video to justify sometime this year not only getting the cam but the brick too ... and the out-board recorder and all ... might be a spendy year ... sigh ... :)

@killagram That's great news.. because I thought it was 1080p 10Bit 422 only now the HDMI spits out 4K 10Bit 422 there won't be a use for the break-out box for my use, unless it's priced right. Got a question you think the new Atomos Blade trully spits-out 10bit 422, or upscales 8bit to 10bit that's what I've heard in the past but not sure.

@Vitaliy_Kiselev thank you for the explanation. Unless the XLR/quad SLI setup is needed, going directly from the mini HDMI port on the GH4 to something like an Atomos or Convergent Design Odyssey 7Q may be the way to go for acquiring 10bit 4:2:2 in both 1080P and 4K. This shouldn't make it too cumbersome with the hot shoe attachment on the top of the camera.

Is the breakout A/V box (brick) necessary for 4:2:2 10bit HD/4K, or can this be extracted via the mini HDMI port on the GH4?

Nope, as I know. If you look at the box it has HDMI connector on the side, so it looks mostly as simple converter.

I wanna say the HDMI spec wont allow anything over 8-bit

It is not true. http://en.wikipedia.org/wiki/HDMI#Version_1.4 Thing is called Deep Color.

I think the future is 10-12bit recording in camera and competitive price. No need for adapters.

Does anyone know if it will shoot log?

I agree but I see around a lot of videos just perfect. Panasonic have always a bad taste/choice with his launch video. Do you remember the GH3 French video?