Exporting QT’s with Alpha into Avid?

[Scott Hathaway]

Here’s what I do using After Effects 6.5 Pro on a PC:

I first open the render queue under Window>render Queue and drag my comp into it. Then I click on the blue text that says “loseless” and to first change the movie format to “quicktime” and then to click on the video output “format options” and change to a codec that renders out with an alpha channel. You’ll know it has an alpha channel by clicking the “channels” pulldown and observing if “RGB+Aplha” is an option. Some codecs with the “RGB+Alpha” option in my version of After Effects are: animation, Intel Indeo Video44, Jpeg2000, none, planar rgb, png, tga, and tiff. I most commonly use the png setting when I want to make lower thirds of a reasonable size with little loss in quality, though the animation codec will get me my lossless video. Then, when I drag my new quicktime onto my Premiere 2.0 or Final Cut 5.1 timeline it overlays nicely. I have never tried it with an Avid.

And that’s how I move After Effects videos with alpha channels to my NLE.

[Dan O’brien]

Are you rendering using an Avid codec? If so, here’s something that may be causing your problem…

First, make sure your comp is 720×486 D1 NTSC, because Avid Uncompressed or Compressed codec requires it. And make sure in the render queue you have rgb+alpha selected with the proper alpha settings (premultiplied for hard edges, straight for soft edges and gradiation)

Second, if you’re using any Avid codec to render out your quicktime from AE, then make sure when you import into Avid you select “use existing” for your alpha channel option. Many people instinctively select “invert existing” out of habit, but the Avid codec in the quicktime already inverts it as it should be.

You can also invert the alpha after importing it into Avid if you need to. You place the clip into your timeline, open up your effects editor, and invert the alpha from there.

If this doesn’t help, give some more details about what your trying to do.

[David Fleury]

Let me try the avid codec / comp size issue. as far as I can tell by responses Ive gotten 5this could be the only thing I havn’t checked or tried yet.

thanks