Quoting "scott s." <[EMAIL PROTECTED]>:
I seem to be missing a basic concept. If I open an image with alpha
channel, I can't find any way to edit the alpha channel. I end up
using other software to save the alpha as a grayscale and editing that.
That requires converting my 24 bit image to grayscale too so I can
load the alpha as a layer for editing. What I want is to keep the
24 bit rgb image and edit the alpha as an 8 bit layer.
FWIW, I generally use 32 bit targa format for editing image with
alpha., because I don't have any filter for directX compressed
formats (DXT1, DXT3).
Perform a "Layers->Mask->Add Layer Mask" and select "Transfer layer's
alpha channel" as the initialize option. You can then edit the "alpha
channel" by editing the layer mask. When you wish to transfer your
edited layer mask back to the alpha channel, perform a
"Layers->Mask->Apply Layer Mask".
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