I am a noob with Photoshop and have really used it for the first time for a character skin. I was always a PSP user but decided to take the plunge I have made a separate black/white image as an opacity map for 3ds max. Now that I want to get the model into UT2k4 I want to turn this black & white image into the alpha…
Go to the channels palete. Create a new channel - this is an alpha by default. Paste the black and white image into this channel Save the image as a 32 bit TGA
That will of course make it impossible to export the image transparency as alpha and prevent you from exporting alpha when you use the channels to save your selections. If you rename the patch before copying it over you can select both though they'll have the same name in the selection menu.