Alpha channels

[camby]

this may be a silly question, but what is the process in creating alpha channels for compositing in post-production? anyone know of a good tutorial that shows you how to set everything up in max? i know this is probably rookie-level stuff, but that's where i am at right now. thanks!

[STRAT]

as long as you render out from max as a full 32 bit image (ie, tga, tiff, bmp) then the alpha channel is automatically included.

 

in photoshop goto CHANNELS or use the LAYER box and the colour channels will be there. the alpha channel is the black and white channel.

[Wolf]

Exactly what Stratt said, or you can do it in Video post or after effects, or any editing or comping package for that matter

 

heres a link to an old tut ive done

 

http://www.angelfire.com/scifi/wolfslair/battletutorial/Tutorial1.html

 

(if the link doesnt work, Copy and paste the url)

[HeDaCoM]

STRAT: this doesn't happend in photoshop 7... why? If I open a 32 bit TGA file in PS7, I have a one layer image with alpha as a load selection set but I can't see the image where alpha is 0 ( background for example). There is no alpha channel. I cannot see the whole image! just the alpha masked one. the rest is a grid of squares.

[nisus]

Hi Hector,

 

I know this problem, but I don't know why we got it that way. Save to tiff instead or alpha split on saving as a tga.

 

nisus