Panasonic Lumix GH2 is stressing the codec too much AND HDMI out is throwing up some surprises…

Posted: February 26, 2011 in colorbyjorg
Tags: , , , , , , , , , , , , ,

EDIT: Sorry! I posted the wrong URL to the GH2 HDMI fix. See below for the corrected link.

I own a Lumix GH2 already since december 12, 2010.

I have been discussing this camera with friends (and a lot of new twitter and blog friends) ever since. The resolution is great, the noise is OK and somewhat more pleasing to the eye than the noise some other cameras produce, and the dynamic range is not bad at about 7,5 to 8,5 stops – depending on which ISO and which method of measurement used (IN VIDEO MODE).

If it wasn’t for the weak AVCHD codec at approx. 24Mb/sec, this would be the best super mega mega DSLR for video use.
Why does the codec fall apart? 24mbit should be OK for AVCHD at this resolution?! Indeed, but the image of this camera is TOO sharp and too detailed.
Using a flat profile and dialing down the sharpness does still produce a too sharp image that has ugly electronic halos and ringing, amplifies the noise and stresses the codec to such an amount that horrible compression artifacts show up in parts of the image where they are best visible: in the grays and blacks.

Panasonic, please give us SHARPNENING OFF. This is so depressing: I have beautiful detailed footage, but swarming with macroblocking (those big coloured compression blocks) and micro blocking (typical jpeg-like strange garbage around detailed areas). This all because of the extreme detail in every part of the picture. If i zoom in 100% on bricks or skin, i can see into every pore. Something i’ve never seen with pictures from my 5Dmk2.

But, hey, a solution seemed at hand: the Nanoflash or Ninja external recorders could record the signal from the (“clean”) HDMI output! But, alas… the hdmi output on the GH2 seems to be crippled in an ugly way (messing up the interlace cadence; adding double interlaced frames each 7 seconds, or skipping frames each 7 seconds). Both the Nanoflash and the Ninja recorder can record the 1080i60 signal including a 3:2 pulldown – that’s OK –  but the recorder wil go crazy if the interlaced cadence is (randomly) messed up approx. every 7 seconds. The Nanoflash will stop recording. The Ninja is not yet available but i assume it will do the same. Normally, FCP or most other NLEs are capable of removing the 3:2 pulldown and Bob’s your uncle. If your’e clips are shorter than 7 seconds… no problem…

So, what to do now?! I was pretty depressed after finding this out. Imagine!! A GH2 + Ninja is a sub 2000$ full HD 4:2:2 high detail camera! A kind of mini scarlet for a 1000 bucks.

I will write Panasonic about this and report it as an error, just to trigger a reaction, but i assume it is a built-in trick to prevent recording from the HDMI output.
Why? AF-101 .., that’s why. At least, that’s what i suspect. You could build yourself a min-af101 for a third of the price, with better video recording. If this is the case, Panasonic is missing the point; that DSLR film makers are NOT per-se AF-101 buyers.
I know people that can afford an AF-101 but stick to their 7D. It’s what they like best and, of course, it’s a totally different market segment budget-wise.

So what should we do?!

- write panasonic and report an error in the HDMI cadence mechanism
- write to sales@atomos.com (makers of the 900 dollar 4:2:2 prores hdmi recorder) and ask them to please please please make the device’s firmware compatible with the GH2

Interesting links:

One point of light at the end of the tunnel (not a train…): someone who does not want his name or position to be disclosed, gave me a hint: “some people” are hard at work to make the GH2 work with the Ninja recorder. But i haven’t said that of course.  Nobody can promis anything, although things are looking promising…
That’s as vague as the general new Scarlet announcement, only without a new price tag…

Jorgen.

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Comments
  1. Ted says:

    Yep Jorgen, I 100% agree ! Any news about your 2K DCP ? You don’t have to find a way to post it online, it would be nice to be able to download a few 2K stills, that’s enough. A question though : how did you enlarge the 1920 width picture to 2048 ? After Effects bilinear ? Or an enlargement plugin ? Thanks !

    • jorgescher says:

      Hello Ted.

      No, it’s much simpeler than that, but i’ve not fully decided which route to follow. The MAIN problem is, that it’s dull rainy weather here for almost a month now. It’s dark and gray every hour of the day. I need to go out and shoot some nice footage and use that for my further tests. It’s raining today and it will be raining tomorrow. So i first want to get that right before i can show anything.

      Jorg.

  2. Dave Shapton says:

    The Ninja will record pretty much any valid signal coming across an HDMI connection. It will also record any rubbish in the image, and no technology can replace missing frames or other weird stuff that comes across.

    We’ve found something that I think is very significant: Almost all video cameras give a nice clean HDMI output that we can record and in so doing bypass the compression in the camera.

    None of the current Canon DSLRs give us a clean signal, and we’re testing a whole range of other DSLRs as quickly as we can.

    But it’s clear that the video manufacturers are happy to let us work with them and the DSLR makers are less so.

    We suggest that frustrated potential Ninja customers politely lobby the manufacturers.

    Dave Shapton
    President, Atomos Europe

    • jorgescher says:

      Dave.

      Thank you very much for your response. Your answer is clear and exactly to the point.
      I hope that GH2 owners will either come up with a postproduction solution or find their way to Panasonic’s tech development department; although that seems a tough route to follow.

      Kind regards,

      Jorgen.

  3. How’s your 2K GH2 workflow coming along?

  4. Ron I says:

    Sorry I should have clarified: what do you mean by “better video recording?” Does the GH2 produce a nicer picture? Or is it easier to use (better operation)?

    • jorgescher says:

      Ron.

      If you don’t take aesthetic illusive factors in account (shallow DOF of the 5D), the GH2 delivers a far more detailed and – indeed – better image in every respect EXCEPT for signal-to-noise at high ASA values.
      I must say that all shots i’ve made with a 7D at low light were horrible too, but that could’ve been my lack of craftsmanship ;-)

      Jorgen

  5. Dmitry Kitsov says:

    I was talking to one of the Atmos guys at NAB. At first he told me that the Ninja is fully compatible with GH2 (as a matter of fact one of the Ninja recorders was mounted on top of the european model GH2). When I started pressing him on a cadence issue he seemed to backtrack his GH2 compatibility statements. Also he flat out stated there will be no peaking functionality.

    • jorgescher says:

      Dmitry.

      Martin Beek at Marvels Film has put up an interesting article today about this issue at http://marvelsfilm.wordpress.com
      Martin and i myself do both own a GH2 and a Ninja and i for myself can say that the picture is better on a few points, but also involves a tedious and time absorbing workflow that only works on a PC.
      It’s a difficult matter. I haven’t still decided if i keep the GH2 or continue saving money for the AF101.

      Jorgen.

  6. [...] biggest problem of the camera and many were hoping for a new hack ever since the GH2 was released. Jorgen Escher put it nicely when he said: “If it wasn’t for the weak AVCHD codec at approx. 24Mb/sec, [...]

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