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majestik__12
03-10-2006, 09:59 PM
Hi, I am not sure if this is the best place to ask, but I am working with an editor on a commercial. I am providing animated 3d models to him that he will put into final cut pro. However, we have not be able to figure out how to get alpha channels to work in FCP. I have tried importing video files that have RGBA(but that doesnt work because the video is already premultiplied) I have made a track of just RGB, and one with just A. I am tried all the blending modes, and masking filters. However all the filters I can input a mask, or multiply another track with let me drop the alpha channel video file in, but it doesnt seem to animate, it will only use 1 frame. Otherwise, The editor has to give me a file with just the background, then I have to put into after effects and render out the models with the background, then give that to him to put back into FCP. And it is just not going to work that way, or be very effecient. Does anyone have any suggestions, or where I could find the answer? Thank you for any help.
adammendyk
03-12-2006, 11:59 AM
Hi, there are many ways to bring an alpha to fcpro. If you have separate sources (fill and alpha) you need to place fill in the v2 layer and alpha below on the v1 laver - then set the fill mode to traveling luma. That's it.
Other way is to import clip with an alpha and that should just work. The question is if you are using codec that carries an alpha such as animation.
Problem starts when you want to import sequence of tiffs or targas. In that case first thing to do is to open it as a sequence in quicktime player (cmnd+shift+o) and save is as a self-contained movie and then import to fcpro.
I hope it'll help you.

rgrds,
Adam Mendyk
majestik__12
03-15-2006, 07:06 PM
Thats so weird, I had brought in a movie file, that used a compression that had alpha channels from AE, but that didnt work in FCP. However, doing it straight out of a quicktime, image sequence to a self contained QT .mov, worked in FCP. That was the only thing I hadnt tried. I had tried the traveling luma matte before, but that didnt work either. Perhaps I messed something up. But regardless, it works now. thanks a bunch.

Here, is a second question I might as well ask, whenever I render maya files with an alpha channel, And then, import them into FCP or AE, there is always a black tiny black outline around the images, it seems it is a result of the premuliplication being done in maya. The only work around i have found is doing a minmax on the images in AE, to shrink the alpha channel. I know there used to be a menu in maya to render rgb, and a to two different image sequence ( mulitpass rendering) but the option is no longer in render settings. Or it has been moved and I can no longer find it. Does anyone know what the issue could be, or where the multipass rending went? Ill ask this question in the correct forum as well. Thank you
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