View Full Version : Still Keyin'


Max Kaiser
January 9th, 2007, 05:31 PM
Hi there,

A few weeks ago I had asked about keying in After Effects. I've been really slugging it out for a green screen commercial and getting okay results when I want stupendous.

Basically, I shot the footage 1080i60/35mb at about F5. I'm trying to key out a well-lit background so that it appears my actors are on a white background.

The key is working fine in AE, using Keylight. The problem is - I get these "crawling" edges that I just can't seem to dispose of. I've bought a book on keying in AE (After Effects studio techniques) and haven't been able to fix my problem. I want solid edges. It is particularily bad when the actors have slightly frizzier hair.

I've read that the XDCAM HD is a great keying camera, and I've read that no one in their right mind would key with an HDV camera.

Has anyone done some serious keying and do they have a recipe for me?

Thanks - I also have Shake and could do it in that if it proved to be better with Primatte.

Thanks!
Max

Nate Weaver
January 9th, 2007, 08:18 PM
Is After Effects interpreting the interlaced footage correctly? That is, it's understanding your source footage to be 29.97 interlaced, upper field first, as opposed to seeing it as 29.97 progressive

If not, the crawling edges you describe could be AE not sorting your source into two separate fields first.

Jim Montgomery
January 9th, 2007, 09:06 PM
Try this

http://www.creativecow.net/articles/kramer_andrew/colorkey/index.htm

Takes a while to get through the commercials, but well worth the effort.

Jim

Max Kaiser
January 10th, 2007, 04:35 PM
nate - yes, I'm being sure to check that AE is interpreting correctly. I actually set the interpretation to upperfields, with preserve edges on. Just for fun, I tried turning it off and it didn't look any better.

jim- thank you for that link. That is some good information, and well presented. Unfortunately, neither of those techniques was enough to get rid of the crawl. Pre-screen blur and a little choke is just the recipe, but it is just not enough. I still see a lot of crawl even in SD - don't even mention the HD.

Anyone had good results?

One thing I'm realizing is that I'm reading repeatedly that I should have shot in 24p. Oh well, live and learn.

Thanks,
max

Jonathan Ames
January 10th, 2007, 06:51 PM
We keyed the entire season of Cowboy Mounted Shooting when we were shoting the color commentators "in the booth" using 3 JVC100HDs and had absolutely no problems at all. I don't have the solution but did want you to know that we've keyed with both the 100HD and the 350s we shoot with now and the results are perfect so it can be done with either level of camera.

Max Kaiser
January 10th, 2007, 07:16 PM
Perhaps I could post a very short clip of the video we shot. Maybe my shooting wasn't so good or something. Would there be anyone that could take a hit at it?

I really want to get to the bottom of this situation as this is something we do quite a bit.

Thanks!
Max

Nate Weaver
January 10th, 2007, 08:28 PM
At least post a still at 100%

Jonathan Ames
January 10th, 2007, 08:54 PM
Nate's correct. Let's see the symptoms and maybe we can come up with a cure.

Jay Chance
January 11th, 2007, 01:26 PM
Are you using the XDCam codec in AE or are you using DVCPro HD etc.?
I've noticed the the native XDCAM 35mbs codec works horribly in AE. I have not done any green screen compositing yet. When using the native codec I noticed an immediate degregation in the footage and you cannot render (at this point) in the native 35mb codec, it won't playback. I'm told it's a quicktime issue at this point.

I had to redigitize my footage in the DVCpro HD codec and I got very good results.

Anybody else having any success with XDCAM in AE?

Max Kaiser
January 11th, 2007, 03:25 PM
Hey there -

Please see a screen still in .png format (I hope this is the right format, I could use something else) at http://www.handcrankfilms.com/images/C0062.png - this was taken directly from my XDCAM 35/mbr 1080i60 timeline.

I'd be happy to post a very short clip of the jaggies I'm getting if that is needed. Just let me know what format I should post 'em.

Jay -

I'm really glad you brought this up. I brought this up about a month ago when I was doing tests but people kept saying how great XD and AE were working together. My results are the same as yours. I did finally wind up converting to DVCPROHD, just as you have, to get even halfway decent results. Yes, AE will recognize and even play (sort of) my XDCAM 35, but the jaggies are pretty brutal. And, yes, I can export in the XDCAM 35 codec from AE to FCP, but again, as you say, it will not play back in realtime even though you get a gray (as in "render ready") bar.

I really have tried every concotion of ways, doing everything solely in XDCAM, converting to DVCPROHD, etc., etc. Of course, if other people are getting good results, then there is still something I'm missing.

Thanks very, very much fellas.

Max

Alister Chapman
January 11th, 2007, 03:27 PM
What are you monitoring with? Crawl is often a monitoring issue.

Max Kaiser
January 11th, 2007, 03:49 PM
For NTSC monitoring, a Sony PVM14M2U, for HD monitoring, Apple 23" HD.

BTW, you can see the crawling pretty clearly even in the AE preview composition window.

Thanks,
Max

Nate Weaver
January 11th, 2007, 05:28 PM
Define crawling.

Is it what you see on the edge of his forehead and nose?

Max Kaiser
January 11th, 2007, 05:35 PM
I see that there, but no. Really it is along the edges of her hair for one thing, when the key is in place and the footage is rolling. Basically, it looks like little ants are crawling along her hairline. Very, very little ants. In a freeze frame, you wouldn't see it. I just posted that image so that people could see that it was in fact a decent key setup we were working from.

Thanks,
Max

Greg Boston
January 11th, 2007, 06:15 PM
I would suggest shooting in 30P and see what you get. I suppose the 60i can be leaving you with some ugly 4:2:0 artifacts. Adam Wilt seems to think that progressive scan is better for 4:2:0.

-gb-

Rob Stiff
January 11th, 2007, 09:32 PM
Max, thanks for the screen still, it keyed out nicely in Final Cut Pro.
I then added a little "edge feather" that gives it a nice look too.

I am also guessing that After Effects will work better with progressive
footage for what you are wanting to do...

Max Kaiser
January 12th, 2007, 06:11 PM
Thanks guys, and yes, next time I'll shoot 30p. I don't know why I didn't think of that!

I'm wondering if there are any filters that could convert the 3 other commercials I have to a "p" format? I know Nattress makes something like this? Would it conceivably work to convert it to like 30p and then do my key from there?

Rob,

I eventually wound up kicking Keylights pre-matte image blur up to about 11.2 to help feather the edges. Frame by frame, looks fine, in motion, you just get these crappy moving edges.

Max

Max Kaiser
January 17th, 2007, 03:31 PM
Just one final post to say I found a great solution. I used Nattress plug-ins to convert the 1080i60 footage to 24p before going to aftereffects. The result? Perfect edges and an immediate and easy key!!

The only problem now is I'd really like to convert to 30p, not 24p but I can't for the life of me figure out how to with the plug in.

Anyone use these things?

Max

Max Kaiser
January 17th, 2007, 05:38 PM
One final, final note. Graeme Nattress came through and steered me to Film Effects and got the 30p I needed. Looks great.

Don't mess with interlaced and green screen!

Max

Nate Weaver
January 17th, 2007, 11:30 PM
At the end of last week I got the call to shoot a bunch of green today, which I just got home from. Jaclyn Smith (!) was one of the subjects, which I didn't find about until 60 minutes before. Yow.

It was just single people on a screen to be composited with motion graphics for a reality show open. Final delivery is in SD, so any 4:2:0 colorspace issues should be covered up in resizing the shots down to SD in After Effects. Hopefully.

Director loved the ability to check takes quickly, as well as overcranking on a couple shots. Final product will air on Bravo in a couple months.

Max Kaiser
January 19th, 2007, 04:21 PM
Congrats, Nate. Please let us know when it will air.

Max