How to make an Alpha Channel with Photoshop
We assume that you already finished a shirt or whatever in PS and saved it as a psd-file. The background layer is set to black, above the other layers of your shirt. This is our starting position.
Click the eye icon in front of the background layer, so the eye disappears. That means the background layer is no more visible. You can see it on the picture – the black colour disappeared.
Be sure that only the layers you need for the shirt are visible, right click on a visible layer and choose “Merge Visible”.
All visible layers are merged to one layer now. Now click the eye of the background layer to make it visible again. This avoids ugly white borders around your shirt in SL ( by the way, it took me a long long time until I hit on that, to be honest, I know that since I make caps with hair, that’s not a long time ago 🙂 … ) .
Rightclick the box in front of your merged layer and choose “Select Layer Transparency”.
Go to “Channels” and “Save Selection as Channel” (the little icon at the bottom with the circle in it)
Go back to the layers and be sure that the shirt layer is marked. Then go to File – Save as…
…and save it as Targa (tga).
After saving you are asked which resulution you want. Always choose 32 bits/pixel. Compress is unmarked. Click OK, and that’s it! Now you can upload your shirt to Second Life.
With a little practice it’s a matter of a few seconds to create an Alpha Channel. It’s really no big deal I think.
In the course of time I will post you some more Photoshop tutorials, if you are interested.
Until then I wish you a lot of fun trying out the Alpha Channel!
Yours, Jamie Holmer