How can i turn a greyscale image into a black to transparent image?

[Gian V.]

I once made a jaket that had multiple colours into one color, for this i somehow turned a greyscale image of this jacket into an image where the Image nolonger was greyscale but from black to transparent, then i easily layed a colour a level beneath this and the jacket now was one colour. does someone know how you can thurn a greyscale image into a black to transparent image?

[Progressive Graphics VB]

Try clicking on the layer of the image and making it Multiply in Transparency settings on the layer palette.