Greenscreen test with (slightly) poofy hair

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Policar

Carbonite Member
I was working on some keys for my upcoming short movie, and in one shot I had to key some poofy hair...normally pretty hard to do with DV.  Here's my first attempt at the footage.  The Key still doesn't look quite "real," and the light doesn't match up, but I'm pretty pleased with the results, especially considering this is DV:

http://home.comcast.net/~pfhorwitz/greenscreen.mov

The scene file settings come in particularly handy when greenscreening; I have my f6 mode specially set up to be optimized for 24pA greenscreened shots.

Btw, the background is just a still image with some fast blur and some noise.
 
Re: Greenscreen test with poofy hair

Re: Greenscreen test with poofy hair

The keying is actually really good. The problem you are having is with your lighting. There is too much green "spill" on the actors face. Since the background is really warm, the green on his face really makes it stand out (not in a good way). YOu might try moving your actor farther away from the green screen so that the reflected light from the screen does not apear on his skin/clothes. There are also some other lighting techniques that can be used to really separate the actor from the green screen without having spill.
 
Re: Greenscreen test with poofy hair

Re: Greenscreen test with poofy hair

The keying is great but I do see the spill. Wow. I love our little DVX.
 
Re: Greenscreen test with poofy hair

Re: Greenscreen test with poofy hair

You're right about the spill--I see it more now that I'm using a different monitor (LCD vs. CRT). I can't re-shoot, unfortunately, but I'm definitely going to try and color correct it out.

Anyhow, that's why this footage is the test shot. And I've tried keying with a GL2, and while the results were decent, the DVX really does seem better and more versitile.
 
Re: Greenscreen test with poofy hair

Re: Greenscreen test with poofy hair

Ooops, I phrased the whole "test shoot" thing wrong. It's basically just a test composite with a little footage (I shot a lot more, only keyed a little), not footage from a test shoot, unfortunately.

It's almost 4am here on the east coast, though, and I'm tired, so you'll have to forgive me.
 
Re: Greenscreen test with poofy hair

Re: Greenscreen test with poofy hair

..you know what disappoints me about this. i was expecting really poofy hair. but it wasnt that poofy. the keying was cool though. but the hair.. yeah.. not that poofy.
 
Re: Greenscreen test with poofy hair

Re: Greenscreen test with poofy hair

I'll fix that right now.
 
Re: Greenscreen test with (slightly) poofy hair

It looks pretty good. I might have missed it but what program did you do the keying in. Adobe After Effects has a pretty good spill suppressor. Were you trying to go for a fake DOF shot? What with the out of focus background, and all. If so, your pretty close. Have to admit I've thought of the same thing before but never tried it. Anyway. keep it up.
 
Re: Greenscreen test with (slightly) poofy hair

I captured in FCP, used the 4:1:1 compression smoother, output to a lossless PNG, and used keylight and the matte choker (and various masks) in After Effects. I didn't use the spill suppressor, although I'll give that a shot.

As for the fake DOF effect, it's sort of what I was going for. This is the close shot in a whole greenscreened scene (I know, I'm turning into George Lucas except without the money) and the wide shots have less fake DOF. It's also because the background is a single low-res image, and it looks pixellated unless I blur it...killing two birds with one stone, I guess.

Oh, and I'm considering greenscreening for fake DOF in another shot, because there's an important focus shift, but I'm going to try to use a lot of light and an ND filter and open iris instead, if possible.
 
Re: Greenscreen test with (slightly) poofy hair

Despite the spill, the key is amazing. This camera kicks serious ass...
 
Re: Greenscreen test with (slightly) poofy hair

Wow! The key works great! This gives me hope!

I'm actually a professional in the visual fx industry, and have had several people at work tell me that "there's no way you are going to get a decent key from a dv image, period." This kind of made me depressed because I don't have the money to shoot 24p HD. Guess you should never say never.

I got a few other greenscreen shooting suggestions from people at work (that might actually be true), one specifically to keep actors and subjects far as far as possible away from the greenscreen (as someone already mentioned), at least 10-12 feet. Also, spill is a spill. I know many professional compositors that struggle with tricky despills all the time, and that is with 2k res images. So it's nothing that you're doing wrong, it's just the nature of the beast.

Anyway, thanks for doing that test! My faith is renewed in this little camera. :-)
 
Re: Greenscreen test with (slightly) poofy hair

That actor is too pretty. Sorry, he's going to have to be liquidated.

:)

Reasonable key though.
 
Re: Greenscreen test with (slightly) poofy hair

Thanks for the compliments! I'm just a 19 year old kid messing around with after effects (but I've spent a very very long time messing around with it), so in the hands of a pro, dv keying can definitely get even better. The most important thing regarding keying with DV, I've found, is to smooth the 4:1:1 compression artifacts, and to try and keep any complex edges (hair, etc.) either significantly darker or lighter than the background (so that this part of the key can be based on luma instead of chroma information.) As for the spill, the actor was only a couple feet from the greenscreen. I should have put him farther away, but I had too much else on my mind during the shoot to remember. I'm still convinced I can fix some of the spillage, though probably not all.

As for my pretty boy actor, he's going to Harvard, so he's smart too! Also a good actor.
 
Re: Greenscreen test with (slightly) poofy hair

Policar, nice job, this is a surprisingly good composite. The comp itself has little to do with the camera that shoots it and more with the fact that its 4.1.1 and the way that you light it.

The best color space for blue/green screen extraction is obviously 4.4.4, a mistake that DP’s often made when shooting 4.2.2 blue/green screen shots was to light the background screen with green fluorescents, this exacerbated the problem by overdriving the green channel and causing a sharper edge – which appeared as a black line similar to what you have on the right side of your actor.

As a rule of thumb, you want a stop and a half difference between the foreground and background. Light the background as flat as possible with white light, the color temperature depends on what kind of scene you are trying to match. It is not always possible to significantly separate the actor from the background, which can give you shadows on the background, and spill on the foreground, there are plug-ins for AE and FCP from Ultimatte (I recommend) and Primate, both of these programs give you excellent tools for spill suppression, pulling mattes on unevenly lit backgrounds, and color matching - http://www.ultimatte.com.

These tools yield a much better result than what you can get with FCP or AE on their own, so if you have a lot of green screens either is worth the investment.

Good luck. 8)
 
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