Big Files and White Outline from Key

[Darby Edelen]

[E Klassen] “I’m happy with the key quality, but when I make a movie with settings RGB+Alpha and Straight Matte (everything else default)”

Do you mean with Straight Alpha?

[E Klassen] “I’m getting very large files (about four times as big as the source)”

The file size will depend on what codec/quality you are rendering to. Since you are rendering RGB+Alpha I would guess that you’re also rendering to a codec that supports Alpha. There aren’t many of these, and they generally use lossless compression at their highest quality so the result is very large files relative to DV or another highly compressed codec.

Your best solution for this might be rendering to TIFF using RLE compression, which is lossless but compresses areas of solid color down very well (there should be lots of areas of solid color if you’re rendering keyed footage).

[E Klassen] “and a bold white outline around the keyed areas.”

Are you viewing the footage in a media player (Quicktime?) or in After Effects?

Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA

[Eric Klassen]

Darby,

The Straight Matted setting was set in the Color drop down under Video. I was taught that this is a better setting to use if a key has been done. Not sure if it should have been called Straight Alpha.

That explains the large files

I was using Quicktime to view the rendered files.

-How do you copy/paste a portion of a post so it appears in italics and author in Bold?

Thanks again for all your help,
Eric

[Darby Edelen]

I believe the confusion arose because there is a Straight Unmatted setting for alpha and a Premultiplied Matted setting, but I’m not familiar with any Straight Matted setting.

Here’s an explanation of the difference between the two settings:

https://livedocs.adobe.com/en_US/AfterEffects/8.0/WS3878526689cb91655866c1103906c6dea-7f7e.html

Premultiplied footage will look more correct in a viewer such as Quicktime Player, but it will need to be interpreted correctly on import to any compositing/editing programs.

Straight footage will look wonky in viewers like Quicktime Player because QT Player doesn’t really handle alpha, but it should look correct when you import it into a compositing/editing program.

Try bringing your footage back into AE.

“Note: To include any portion of this post in your response, highlight the desired text with your mouse and hit the “Q” key.”

Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA