How do I export a Movie in AE with Alfa Chan

[Kevin Camp]

you’d need to either render to a codec that supports alpha, or render a separate file to use as a matte in pp.

for a codec that supports alpha i’ll typically render as a quicktime lossless animation codec with alpha enabled or quicktime png (.mov file not image sequence), though there are some lossy codecs like prores 444 and dnxhd that support alpha.

regardless of which codec you choose, you’ll also need to enable alpha in the render settings. in the render queue, click the underlined text next to the output module (default typically is ‘lossless’). then from the channels menu select rgb+alpha, and i would also select ‘straight (unmatted)’ from the color menu.

if rgb+alpha is not an option, then you need to change the codec by clicking the format options button and choose a codec that supports alpha.

if you rather render a separate matte file, then from the render queue, set the output module to the desired codec/format for the rgb portion of the render, then duplicate that (select the module and choose edit>duplicate) and click the underlined text and choose ‘alpha’ from the channels menu.

then when you render, ae will render two files the fill (rgb) and the matte (alpha) that you can take into pp and use.

Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW

[Don Cobble]

Thank U ALfa all set, That did it!
If I may ask another question that I don’t know the tech term for what I am saying. Its a Chroma Key Question.
Key Light:
I key the Green : Ok
I choose Matte view : Get the White all Clean : Ok
I get the black all black: Ok
But when I go back to the composite/final view My (Talent that I keyed) has areas (that look as though my white area is actually not clean white) His Black coat is kinda pixilated looking in areas. But If I go back to matte view it is Clean White and Clean Black. But the picture says other wise??????
Can you help me on this? Please Thank U

PC 1
I7 2.8 Ghz 8GB Ram
Win 7 Pro 64bit OS
PNY Quadro 4000
PC 2
I7 3930K 3.2Ghz
32 GB Ram
Win 7 Pro 64bit OS
PNY Quadro 4000

3-4 TB HD
Vegas 10 64bit & Vegas 11 64Bit & Vegas 12 & Adobe Production Premium CS5.5.2 & Avid Media Composer 5.5

Camera
Sony EX1 shoot in 1920×1080 30P

[John Cuevas]

Very common problem with keylight. Take your footage and duplicate it. Delete the keylight effect from the bottom layer and change it’s track matte to “alpha matte”. You get the great matte you created originally, without the noise that occurs when using keylight.

Andrew Kramer has some good keylight tutorials, check out: Basic Color Keying
href=”https://www.videocopilot.net/tutorial/advanced_soft_keying/”>Advanced Soft Keying

Johnny Cuevas, Editor
Thinkck.com

“I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”
—THOMAS EDISON on inventing the light bulb.

[Don Cobble]

Kramer is great help – Thank U
I am not familiar enough with keying in AE to understand what you both told me, but tried and want to make sure I did it correct
1 Duplicated talent layer
2 Key light on top layer
3 Alfa Matte the duplicated layer (no Keylight)
4 Then turn of first/top layer??????

The reason I turned it off is that is when it seemed to make my second layer look ok. Is this correct? because when I left first layer on it still looked bad.

I am a beginner i didn’t even know what or where alfa matte was – but found it!
Thanks for help

PC 1
I7 2.8 Ghz 8GB Ram
Win 7 Pro 64bit OS
PNY Quadro 4000
PC 2
I7 3930K 3.2Ghz
32 GB Ram
Win 7 Pro 64bit OS
PNY Quadro 4000

3-4 TB HD
Vegas 10 64bit & Vegas 11 64Bit & Vegas 12 & Adobe Production Premium CS5.5.2 & Avid Media Composer 5.5

Camera
Sony EX1 shoot in 1920×1080 30P

[John Cuevas]

You got it correct. The top layer with keylight will be your alpha matte. Only where you keyed it, will the bottom layer show through, it cuts away the bottom layers green screen. Using this method will remove the noise that occurs when you use keylight.

When you have set up, you might want to select both layers and pre-compose them(shift+cntl+c). That will put the layers into there own comp and in your final comp you can now work on both as a single layer.

Johnny Cuevas, Editor
Thinkck.com

“I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”
—THOMAS EDISON on inventing the light bulb.