> i have a grayscale image (layer). now i want to add transpary
> to layer (the
> black parts are not the be transparent, the white parts are to be
> transparent, the gray parts are to be 50% transparent. so how
> can i transform (or add) a black and white image to a kind of
> transparency mask ??
You can do this by masking (with a layer mask) the image with the inverse of
itself. In other words make sure that the background has an alpha channel,
copy the image, add a layer mask and paste the copied image into it.
Finally invert the colours of the layer mask.
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