I don't see dramatically better keying from my D800E and Ninja 2 over a hacked GH2 and the GH2 has slightly better detail and less moire. Even lighting and very green background material seem to make more difference.

@paulo_teixeira - thank you for your post! I had seen your video a while back when trawling the net for chroma key projects done with the gh2. Great work for a first-time effort!

My first-time effort was, alas, not shot with a GH2. In fact, after the project was completed, my friend who produced the film purchased a GH2 after we discussed various options for future film projects, so I now have one at my disposal, but haven't had any time to work with it being a self-employed web developer. Hopefully next year some smaller projects can be realized with the GH2- I'm terribly excited to use it, what with an adapter for all my Pentax K-mount manual primes!

So my first ever production to be involved in was shot on a JVC consumer HDV cam (can't remember the model!), which I would never, NEVER do again! A 40 minute film that was entirely composited, every last minute. The film is titled "Lovleighton Manor", was written by my wife's best friend, and we got together with with the best cast we could put together over several weekends scattered through 2011 to shoot the piece. Post started in winter 2011, and final project was done in April this year. My friend and his wife produced the film. I performed all post (audio and video) and worked on the initial editing together with my friend and his wife.

I learned quickly from all the mistakes made in the shooting of the piece, and have to say we're proud that we were able to pull together a decent film that held together despite tons of screw-ups in putting together a chroma key project. All keying was done in Ae with Keylight- some scenes had 5-8 layers of footage (rotoscoped, garbage matted key layers to deal with crap screen lighting, etc), and to top it all off, yep, we shot on a BLUE SCREEN with a consumer HDV cam - it was done with intent since some of the costumes were green, and some scenes had flowers with greenery in them. I'm sure those who have dealt with bluescreen HDV tape compressed footage know what a nightmare that blue channel is to deal with.

The end scene was alot of fun, actually- all the shadows were generated by projecting shadows onto 3d planes in Ae- it was great to add a touch of realism without having to do full 3d rendering!

I threw myself into this project, wanting to get the best possible result out of it for all the effort put into it by my friend, his wife, my wife- everyone put in such great work on this, from the writing to the costumes to the performances. I really feel like it stands up as a decent piece of independent film making.

Keying unfortunately had to go the "lowest common denominator route", where keys were heavily eroded due to very poor screen lighting and the evil beast, wrinkled screen fabric. So I wasn't able to do this in a way that was technically perfect, but everyone who is a consumer (not being privy to the fact the entire film was composited) didn't seem to notice or care that much, and that was huge relief for me- I didn't want all the work that went into this to look so fake that an audience couldn't enjoy the film.

So, moving forward with the GH2, I'm so glad to have a space where others are sharing their experiences with keying- I found the whole process of film making from beginning to end inspiring- hitting the right notes in my skills and passion. I wanna keep going!

Here's the url for the film- it is 40 minutes long, btw, but watch if you wish when you can. We're all proud of it!

vimeo.com/40420578

I've never tried it, but I've pulled elements from a white background before. To me a white key sounds like an absolute nightmare, you're going to have to soften/sort your edges out an awful lot before compositing. Pulling from white by keying the blue channel can work out okay though, but white spill is going to give the same, if not more, problems for you as green spill (its going to 'pop' out more I think). I could be wrong thinking here though, and theres something fundamental I'm missing.

There was a comment made in a clip on a DIY site about lighting (that didn't have to do with keying, I can't remember the site) by the narrator that he used white backdrops for keying. I find that interesting, but problematic at many levels to say the least!

Although it seems that some roto/multi-matte work is going to be the case with almost any keying job- so I guess rotoing a highlight in the "keep" portion of a key with a white backdrop wouldn't be the end of the world. Goes to show you everyone has a different approach!

@willianaleman- That much is true in regards to the color space conversion- 5d to rgb doesn't magically create bit depth that doesn't exist! However, from what I've read on their website, the conversion process from YUV->RGB is more precise than that done by most NLE's or effects packages, so you get a cleaner conversion, and it does some edge smoothing in the process.

I don't have any GH2 footage to test with at this point, but I should have a chance in December at some point. I'm going to try and do some testing with various firmware patches, as well as using 5d to rgb, and see what those differences are (in some kind of controlled way).

@virgilr For me the erosion of fine hair details happens far more when the background is not evenly lit. I can see when trying to lose a particularly nasty crease starts to impede on image quality. Luma and Chroma sliders past about 70% will start to eat into quality.

When this has happened, I've used the blade tool to cut the footage into sections, then crop as far in as possible, then key whatever is left.

I used to import the MTS files directly into FCPx but the latest version is not liking the high bitrate patches, so at the moment they are going through iCamera Wrapper, this doesn't affect the keying at all.

Currently I'm borrowing a pair of LED replacements for the typical 500x500mm office lights. These are powered by 48V and are basically a 500x500x8mm form factor. The light they create is so soft it really helps deal with backdrop creases and folds. Unfortunately the CRI on these is about 80 so they are not good enough to be used as main lights.

@endotoxic- have you found it be helpful in converting with 5DtoRGB?

@Ralph_B Good to know keying the native format files works out well. I had read that 5DtoRGB, in it's process of YUV->RGB conversion, does some very nice edge subsampling/smoothing that can help keying difficult subjects (lots of fine hair, etc).

I appreciate all replies here!

Thank you both for your insights! Good tip on the screen lighting, @andyharris. @Ralph_b- thanks for the information regarding both patched and stock settings. So, it doesn't seem to make a whole lot of difference, then, in terms of noise and "key-able" footage if a particular patch is used?

A couple quick questions for both of you- do you find you have to tweak your keyer settings strongly due to issues with the footage- in such a manner that you start to see erosion of details in the keyed content (such as fine hair detail, etc)?

Secondly- have either of you ever used 5DtoRGB transcodes of your footage, or do you use the footage straight from the MTS files?

Again, thanks to both of you!

Here's my expereience:

1) With the GH2, greenscreen will give better results than bluescreen. 2) Shoot at ISO 160. You want as little noise as possible in the picture. 3) Set sharpness to -2.

I use Sanity 5 as my patch, but I've pulled execellent keys even using the stock settings.