Personal View site logo
Make sure to join PV on Telegram or Facebook! Perfect to keep up with community on your smartphone.
IS GH2 for those filmmakers who wants heavy 3d composition & Greenscreen in their film?
  • Panny FILM MAKERS.

  • 18 Replies sorted by
  • it's OK, but honestly, GH1 would be better as you can shoot 4:2:2 mjpeg with it (which is huge if you're doing greenscreen).

  • Of course, the GH2 is nice because of the clean HDMI, you can use an Atomos Ninja (or similar) to shoot ProRes 422HQ.

  • Except the GH2 does not offer 4:2:2 via HDMI....

  • Not really. There's a fair amount of skew in the footage with even small amounts of motion that make pulling a really tight 3D track a challenge.

  • If there's a fair amount of skew (if I'm not wrong you are [DouglasHorn] saying about "ROLLING SHUTTER" ) in GH2. If so then is Rolling Shutter Plug-ins used for minimizing 5D Skewed footage work here? How far I know GH2 has very little Rolling Shutter effect than 5DM2.

  • Is hack give any added benefits for my Green Screen & 3D tracking? If so which Hack is better for my work?

  • Use the latest hacks from Sir Driftwood and a Sandisk 64GB/95mbps, transcode with 5DtoRGB (or one of the high-end softwares) for green-screen. You should be fine with good lighting.

    Regarding 3D: don't expect too much, RS can be a PITA when doing 3D-Tracking. You can try the RS filter in CS6 or the one from The Foundry, but you'll need to mask out all moving objects (people, cars, trees in the wind…).

    It might be too much work (and additional software needed) instead of renting a better camera for heavy VFX. But in the end, it all comes down to the best balance of time vs. money available …

  • @anupamgroy - Yes, rolling shutter. Warp Stabilizer-type plugins can help but it's limited. If you're going to go to the trouble of doing heavy 3D composition, you will save a lot of time in the long run by using a camera without rolling shutter.

  • @anupamgroy If you have not committed to a camera and are still deciding what to use, then there are definitely much better cameras available for the job and not all of them will cost an arm and a leg to rent or buy. If you are already using a GH2 and trying to find out what to do to get the best shoot out of it, then here are some things I would consider.

    For green screen, set your color profile to vibrant and light the scene so that you have a sufficiently narrow dynamic range on your subject. Use ISo 200 to avoid any chance of the noise bug (or ISO 160 if you are confident you can consistently remmeber to keep track of the bug) to get a wide dynamic range with low noise (at least to the extent possible given the contraints).

    If you are shooting 1920x1080, use 24H (or 80%24H instead of HBR ) to get the best quality you can. For that type of shooting, I would rely on an intra setting from Driftwood, either Sedna or Canis Majoris (in their many variations). If you go for Sedna, I would probably use a Sedna C version as opposed to an A1 to try and get cleaner areas as opposed to more detail, but your mileage may vary.

    If you are shooting 1280x720 at 50p or 60p, there are more options to consider, and the first one I would try would be Mysteron (since it is one of the most stable Driftwood options) or Sanity 5 (since I have used various versions of Sanity to shoot more slow-motion footage than any other setting). There are many other good options, but those have a very high chance of working.

    Other people have addressed rolling shutter concerns so I will not.

    If you go looking for another camera to use for the shoot, do not look at other current DSLR options. Look at cameras that support 4:2:2 or 4:4:4 and 10-bit or higher color with lossless or visually lossless compression options (or "not visually lossless but just plain wavelet, etc.") In some cases these things are offered through external recorders and in other cases onboard. You could also look at cameras with higher frame rate options, depending on your slow-motion needs and your budget.

    But long story short, compression artifacts or sensor noise, low color depth and insufficient chroma sampling can all create a lot of extra work during a green screen session. The GH2 is a great camera but it suffers from all of them in that context. You can still get great results from it, but it requires more work.

    EDIT: I forgot to mention that if you want the highest image quality for keying in very short bursts, the 40 fps SH stills mode is still the best option on the GH2 and better than MJPEG on the GH1 that some suggested. But 40 frames is a prohibitively short burst for most applications.

  • Thanks so much for all your helpful replies - much appreciated.

  • I shot a web commercial with a stock GH2 and I found it to be pretty awesome. I don't know how picky people are, but to me, it seemed really really good for green screen. And that was with NO hack applied!

    If you know what you're doing in the NLE you should be fine.

  • X_worpig_X ...... may I see your Greenscreen Clip..before Chroma & After Chroma. Without any compression... just 3 to 5 second only.

  • @anupamgroy

    Green screen is something that needs to be done well on set! Regardless of camera used. There is issues with 420 v's 444- but the newest Settings fix this up a huge amount!

    What does NOT get discussed in Greenscreen threads is that getting a good key is only half of the problem. Many times S#@t happens on set and you can't just chuck out a good performance. This is when green screen just lets you know where to 'cut'. Like wire removal some things just take time- frame by frame retouching- and a Wacom tablet. YMMV.

    Youtube keying for professional movies you can find some crappy keys that turn out super!

    Just like if you work at a post house and look at low light digital footage 'restored'.

  • @anupamgroy

    Green screen is something that needs to be done well on set! Regardless of camera used. There is issues with 420 v's 444- but the newest Settings fix this up a huge amount!

    What does NOT get discussed in Greenscreen threads is that getting a good key is only half of the problem. Many times S#@t happens on set and you can't just chuck out a good performance. This is when green screen just lets you know where to 'cut'. Like wire removal some things just take time- frame by frame retouching- and a Wacom tablet. YMMV.

    Youtube keying for professional movies you can find some crappy keys that turn out super!

    Just like if you work at a post house and look at low light digital footage 'restored'.

  • @anupamgroy

    Green screen is something that needs to be done well on set! Regardless of camera used. There is issues with 420 v's 444- but the newest Settings fix this up a huge amount!

    What does NOT get discussed in Greenscreen threads is that getting a good key is only half of the problem. Many times S#@t happens on set and you can't just chuck out a good performance. This is when green screen just lets you know where to 'cut'. Like wire removal some things just take time- frame by frame retouching- and a Wacom tablet. YMMV.

    Youtube keying for professional movies you can find some crappy keys that turn out super!

    Just like if you work at a post house and look at low light digital footage 'restored'.

  • Thanks ALCOMPOSER. I have very short budget for my short film. I'm agreed that evenly & fairly lighting Green screen is the main secret regardless of camera used. Ya, bad lighting mess the Keying process even though using 4:2:2 or 4:4:4 footage.

  • Now the question is that if I buy a GH2 am i miss something? Or am i getting some problem in post? When I have no budget to buy a BMC Camera which gives 2.5K and 4:2:2 Color Space.

  • Keying is always a painfull task using DSLR Footage. I have done keying and compositing on 60 shots shot on 1D Mark IV for a long feature film. You really have to be very careful not to end with crap. Yet it is possible to do it, here's some making of I made :

    GH2 codec is not worse than Canon, especially with the enhanced quality brought by Vitaliy hack and Driftwood awesome patches.