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B&W image to alpha channel

Mar 21, 2012, 23:16
Post: #1
B&W image to alpha channel
Hi,

I have a B&W images. It's actually in RGB but all shades are gray. I would like to create an alpha channel whose values equal the brightness of each pixel.

How do I do that?

Thanks!

Sam
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Mar 22, 2012, 00:09
Post: #2
RE: B&W image to alpha channel
Thanks.

I tried the equivalent second approach, but I am not sure it worked. After I copy a channel by dragging (now I have "Blue Channel Copy") what makes it into the alpha channel?

Thanks again,

Sam
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