[Kenneth Kirkpatrick]

Chris:

Thanks for your post.

I’ve tried all your suggestions. I was able to get it to output a clean, uncompressed, unkeyed clip as per your suggestion.

But when I take that clip and run it through Keylight with lower field output, whether to a Quicktime or an image sequence, I get the softening effect. I can get a better looking render when I use no field. It is crisp, but there is still detail loss because I’m missing a field. That is acceptable for this project, which is for the Internet.

But I still want to know why this process, which has worked so well before, no longer works. Also, I’m still having the other problem of AE constantly crashing while I’m rendering: I can’t leave a render queue going overnight, and I have to constantly babysit the render.

Thanks.

[Kenneth Kirkpatrick]

Yes, that’s the first thing I do. That’s what’s stumping me now. If I don’t interpret it I get all kinds of problems. We use Beta to record our chromakeys (it’s cleaner than DV) but I don’t have the option with Beta to shoot progressive.

I have to interpret fields, or I get field blending problems. Assigning field order doesn’t seem to be the problem. Rendering with field order, no matter what output choice I make, seems to be my problem.

Thanks for your response.

[Kenneth Kirkpatrick]

Dave:

Thanks for your reply. I tried a couple more test based on your comments. I rendered out a segment of the original clip to a PSD sequence. Then by mistake I rendered out a clip of the chromakey (using no compression) without using lower-field-first. It looks fine. When I rendered it again, exactly as before, except using lower-field-first, it looks blurry. I’ve tried several ways, now: PSD to uncompressed, uncompressed to uncompressed, etc., and it’s only when I used a lower-field-first output that I get the softening issue.

Have others encountered this in AE using field-rendering? I have to use field-rendering, don’t I, when using interlaced footage, to avoid field-order issues?

Thanks

[Kenneth Kirkpatrick]

Did you create the panels in a single Photoshop document?
Did you export that as a comp, not as footage?
Did you set each layer as a 3D layer in your comp?

[Kenneth Kirkpatrick]

I have been having crashes with Keylight, too. Have you had any softness issues in the final render?

[Kenneth Kirkpatrick]

Have you tried doing a difference key in a precomp? Is there some footage shot of the set before the talent was on camera? (It has to be with the camera in the exact same position as with the talent.) Try grabbing a frame (or looping a small section if possible.) Then you can set that or the talent footage as a difference layer above the other. Don’t know how well it will work, but I have been able to use the technique successfully on a couple of occasions. With some more tweaking it can sometimes be used as another matte key.

[Kenneth Kirkpatrick]

What happens when you mix 720/480 with 720/486? I’ve posted about this, but didn’t get a good answer. I’ve had this same problem, with stuff from DV being sent out to me at 720/486, with either a black bar at the bottom or the fields blurred when expanded. I am a graphic artist, and I do post effects on quicktimes our editor sends out to me.

How do you keep your Avid edit at 720/480? I keep rendering my graphics at 720/486 because DV won’t render with an embedded alpha. Does adding footage of 720/486 force an edit to become that size?

[Kenneth Kirkpatrick]

In the past I have had our chromakeys shot on our Betacam camera back, which is 720/486 when captured using the Meridian codec. That pulled good keys. But the Betacam format is no longer supported, and the last time we used the camera back it screwed up the video because it’s worn out, and it isn’t worth fixing.

People can and do use DV for chromakeys. My questions were aimed at Avid users who do. How do people get Avid to export video at the same resolution at which it was shot and captured?

[Kenneth Kirkpatrick]

But then how do I get decent video for posting? For instance, we did a chroma shoot that was all jacked up because the fields were blended together. How do we keep a sequence locked in at 720/480?

[Kenneth Kirkpatrick]

Try rendering the matte channel out as a black and white movie, and use that separate movie in the alpha channel.