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funkyrayuk
09-02-2004, 01:25 PM
I'm trying to do an animation of my model spinning around which then cross dissolves into the mesh but i'm having trouble doing this.
If i render the video of the two sequences and take them into premiere, when i try to do a dissolve the background is included in it and a noticeable change occurs in the colour.

What's the best way to do this, i was thinking that an quicktime with an alpha channel was probably the way of going about it but i can't seem to get it to work.
jorgevaldes
09-06-2004, 05:42 PM
maybe you didn´t set the color depth to millions+ on the QT settings
Backenbotten
09-13-2004, 12:54 PM
Hi funkyrayuk!

The first thing I would do is to check the channels separately, if you have any means to do that (you could always do it in the rendered frame window in max). Is the alpha channel correct for both of the clips? It should be all black where your background is, and 100% white where the object of interest is. If it is correct, and the background still shows up when you render in premiere, the reason has to be how you let premiere interpret the alpha channels. I am not a premiere user any more, but I used to, and in those days you had to right click on the clip, choose some kind of "set transparency" or something like that, and then choose "alpha" as source for transparency. If you didn't do this, the alpha was always ignored, so there was no automatic use of alpha channels like in many other apps. One more thing, you have to render a preview in premiere for it to process the alpha (at least in my days), it was NOT used in the video monitor window if you didnät hit "make preview".

You also say there is a change in colour. Here I would check my RGB channels, without any alpha, to see if the problem still exists. If it does, it seems like your original color channels in the rendering are different. Are you sure you are using exactly the same material for the objects in your 3d app, and the same lighting setup etc? (except the one render being wireframe of course)

When you render quicktime with the animation codec at 100% quality and millions+ setting, you'll get full quality frames with alpha channel. As, jorgevaldes said, the "+" setting is a must since that indicates that the alpha channel is saved in addition to the RGB channels. Without it, you get no alpha channel.

One more thing you could do to troubleshoot further is to render your alpha in a separate file (grayscale 8 bit), and then set that file as alpha source in premiere (if that's possible).

Hope you can solve it!
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