FS-100 greenscreening

Small crisis going on here... we did a complete green screen music video with the FS100 and stock lens.

The screen was lit with 3 Kino Flos with green lamps. The talent was lit with two Kino Flo 4ft 4banks and we used 2 lights gelled warm on the back of the talent.

The video is build up so that the main talent goes in a white room and the secondary talents go in a black room. The editor had no problems pulling the key off the main talent to the white room, but he's now looking at the "black" talents and the results he gets when pulling them and placing them in the room is that they get pixilated in the edge. They key will eat part of the talent here and there, and then a couple of secs later it's normal.

I didn't have an immediate answer for the editor regarding this, because I have never experienced it before. What could be causing this? I read somewhere that too hot backlights can cause blockiness, can it be that simple? Did we simply overexpose the backlights?
The screen lights were flagged off and angled away from the talent, so I can't imagine they would cause problems.

The editor said that he had already converted the avchd to prores 4:2:2 to see if that could conjure up some latitude, but to no luck...

So I hope anyone here has some ideas if this can at all be fixed in post with some specific settings in AE (the editor is using KeyLight) or if we have to redo the secondary talent shoot.

Tech data:
1080p
50fps
Iris 8
shutter no less than 1/60
AVCHD to card
on tripod
 
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I've been looking through some of the various DVX archives on FS100 and green screen but I have a question or two.

I have an upcoming shoot which will be fairly similar to what alaskacameradude posted with the police video. Most likely waist-up, talent addressing the camera. No movement.

I would like to use the FS100 and kit lens on a studio green screen.

For post, I am planning on using Keylight. My workflow usually involves transcoding to Prores for a FCP edit.

Does anyone have any particular profile settings they can share that they've found work good for keying? (ie, sharpness, black levels, gamma) Or anything I need to watch out for? This is a corporate video project, nothing of cinematic proportions, but I want it to look nice.

From various examples I've seen round the web, it looks like the FS is capable of producing keyable footage if things are done properly.

thanks,
Scott
 
Here's a little secret of mine. I do a lot of keying from all sorts of cameras including quite a bit of FS100 AVCHD footage. There is a plugin called "Neat Video". It is primarily used for noise reduction but also cleans up color artifacts. So, in After Effects, apply NV to your footage then apply Keylight second in the chain. If you do a pre-key with color key or similar, do this first then pre-comp the footage, moving attributes to the new comp. Then apply NV and Keylight to the new comp.

Neat Video will cost you a tiny bit of sharpness. It gets worse the noisier the footage is, so if you shoot clean at low gain and expose properly, you won't see much difference, if any. The plugin has a sharpening feature built in to recover any loss of detail.

I was only using it on 5/7D footage and AVCHD, but it really makes all footage look better. It goes beyond the way your edges look. It prevents keylight from degrading other areas not near the edge. There is green in almost everything. Neat helps you keep the green in the areas you want to keep. Try it and look at the difference in your blacks.
 
http://vimeo.com/35381337

This is link to some recent greenscreen on the FS recorded to internal SD card. It was effortless to pull the matte, I sat with editor and it was a snap. He actually remarked on how easily and cleanly it pulled.
 
Thanks for sharing, Caleb.

I can't share my footage, but suffice to say, it came out very similar to what you posted. I'll be dealing with cleaning up some hair & a few artifacts, but for the most part, it was very acceptable.

It goes w/o saying to get a workable key, it helps to have a nice, evenly lit wall. That's half the battle. The studio we used was fantastic.
 
legrevedotcom said:
but he's now looking at the "black" talents and the results he gets when pulling them and placing them in the room is that they get pixilated in the edge. They key will eat part of the talent here and there, and then a couple of secs later it's normal.
AVCHD to card
Click to expand...
Sounds like it could be compression artifacts that are larger than the object keyed... choking the key and erodeing the edges may be the ugly answer

d
 
Would it be fair to say that keying at 25fps (I'm in PAL land) would be better than keying at 50fps as it works out more data per frame e.g. 24mbps/25 versus 28mbps/50?
 
Pastor Thug said:
Would it be fair to say that keying at 25fps (I'm in PAL land) would be better than keying at 50fps as it works out more data per frame e.g. 24mbps/25 versus 28mbps/50?
Click to expand...

Yes- 28mbit for 50p is quite low compared to 24Mbit for 25p.
Use external recorder to capture 4:2:2.
All prosumer formats (AVCHD, XDCAM EX/HD) are heavily compressed- use at least 100Mbit MPEG2 I frame, or AVC-I. Latest one is on the edge of high quality capture formats, but with specific content can also struggle.
ProRes, DNxHD recorders are cheap these days and they offer way better quality, so if you can use it :)

You can even get one of BlackMagic recorders (they are so cheap) and record to laptop over USB 3.0 or Thunderbolt on MAC. This is possible specially for studio work.
 
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