View Full Version : Anti-aliaising alphas?

04-10-2013, 03:44 AM
Is there a setting somewhere to make my alpha channels not look crappy when I bring them into After Effects?

When I render my object in LW and look at it in the LW viewer the edges look fine. They also look fine in AE if I disable the alpha channel.

But if I use the alpha channel (which oddly enough is why I want to bring it into AE) then the edges get choppy, as well as infused with the bg color.


In this example, the image on the left has the alpha disabled. The image on the right uses alpha, you can see over the colored background that their is a bit of a white halo going on. You cant really see from looking at this image, but even on the white background, if you toggle the alpha on and off (using the AE Shift Channels effect to set alpha Full On) when the alpha is on - your edge thins out a bit and gets chunkier.

Is their a setting when I render in LW, or a setting in AE, to keep my edges looking clean and without the bg they were rendered on?

Does multiplied alpha have to do with this? (it doesn't seem to make any difference in my experiments)

Any help would be much appreciated.

04-10-2013, 04:53 AM
Not sure about a setting but a cople things you could try.
Use a white background in LW instead of black.
Save as another format, (tga or tiff instead of png).

04-10-2013, 08:10 AM
you can also try some post AA... like OLM >

04-10-2013, 08:17 AM
In After Effects, right click your Image sequence, go to Interpret Footage and click Main or select your sequence and press CTRL+Alt+G . Change Alpha to Premutiplied - Matted with Color and next press the Guess Button and Ok.

If you don't do this you can see some kind of halo in your image alpha edges when comping in After Effects.