Jim Brown

@Pixey. Thanks. I'll look at those and let you know how I fared.

Pixey, Again thanks. My specific issue is that my image is anti-aliased and using the magic wand leaves too many semi-transparent pixels (or, doesn't select enough of them, depending on tolerance) around the edges, so my edited image has jaggies or a halo around it. That's why I thought something where I could adjust the alpha channel selection would work better. And BTW, I'm way over my head in what I just said as I really don't understand the way color and alpha work in the selection process.

@Pixey and @kasadia: Thanks. I'll try these plugins out also.

I’m trying to use Jesse Chunn’s Color Replace plug-in to replace a white background with a transparent one. I have tried many settings in the plug-in, but have been unsuccessful. It would seem to me that setting each of the channels to 255 with a tolerance range of 0 would select white, but it seems to select all pixels, i.e., the entire image turns transparent. I hope Jesse Chunn is still on the forum and can answer this question directly. Any help you could give me would be appreciated.