Alpha channel rendering black

Question

Alpha channel rendering black

Something really strange going on.

I have a Macbook Pro, a new Mac Pro, and some external thunderbolt storrage. We use a logoloop on top of our video with a alpha layer. If I render the video on the Mac Pro the alpha channel is rendered correctly (we can see the images below, also in the preview we can see the alpha channel work), but on my Macbook both the preview and rendered file ends up rendering black (we can't see the video below). The strange thing is we are using exactly the same files, project, ... Before it also worked on the Macbook Pro but suddenly it stopped. I can't find any setting in FCP X 10.1 to fix this again for my laptop.

Any suggestions?

MacBook Pro with Retina display, OS X Mavericks (10.9.1)

Posted on Jan 30, 2014 4:40 AM

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Answer 1

Aug 26, 2018 1:09 AM in response to Luis Sequeira1

Hi Louis,

Thats correct for playback, but not for rendering...

Second problem. How do you disable proxy on FCP 10.1, in 10.0 this was a preference in the playback settings... But in the new version this setting isn't there anymore.

K

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Answer 2

Jan 30, 2014 5:27 AM in response to Community User

Maybe that is because in the MBP you are working in proxy, which does not support the alpha channel.

Switch to original/optimized media.

In 10.1 this is done in the viewer. Click the little triangle at the top right.

Message was edited by: Luis Sequeira1

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Answer 3

Tom Wolsky

Level 10

151,022 points

Jan 30, 2014 5:48 AM in response to Community User

Selection is in the upper right of the viewer.

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Answer 4

Jan 30, 2014 5:55 AM in response to Community User

KevinVDS wrote:

Hi Louis,

Thats correct for playback, but not for rendering...

I don't understand what you are saying. The fact is, if you have a clip with an alpha channel the only way to see it properly with the alpha channel is NOT to use proxy media. That is true of playback, rendering AND exporting, as you may easily test. Of course, you can do your edits in proxy mode, but "blindly", or simply disable the logo until the end stages of editing, and then turn it on and switch back to original/optimized.

Second problem. How do you disable proxy on FCP 10.1, in 10.0 this was a preference in the playback settings... But in the new version this setting isn't there anymore.

K

Tom and I have already answered that.

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Answer 5

Aug 26, 2018 1:09 AM in response to Luis Sequeira1

Thx, that indeed did the trick.

Before (10.0) we had set playback in 'proxy' mode, but rendering still used the original files. Now it seems that both are linked.

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