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.

Regards. --
Steve Crane
http://craniac.afraid.org

You dont have to use mask.
Change the layer mode into Multiply. On Sen, 2003-06-09 at 15:59, Andreas Wuest wrote:

Hi,

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 ??

thanks in advance,

Andreas

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Hi,

zeus writes:

You dont have to use mask.
Change the layer mode into Multiply.

Huh? The Multiply layer combination mode doesn't affect the alpha channel at all. How can it turn intensity into transparency?

Sven

On Mon, Jun 09, 2003 at 06:53:26PM +0700, zeus wrote:

You dont have to use mask.
Change the layer mode into Multiply.

This is true if the effect you are trying to achieve is "transparency" over the layer below. However if you wished to save the image as say a png with alpha transparency then I think you would need to use the mask.