PhotoShop TGA transparency problem

I was making transparencies in PhotoShop CS2 and uploading to SL. Now all of my TGA files have a white background including the earlier tga files when opened in PS. I have followed several of Chosen Few's tutorials and created Alpha Channels. The channels look fine until I save them as TGA transparencies. The the files open with a white background.

Since the previuosly made tga files now also have a white background when opened in PS I feel I have made some settings change, but can't recall doing so. The only thing I have done is to uninstall PhotoShop Album. Could this have corrupted PhotoShop in some way?
I have since re-installed PS Album , but it had no effect on my PS transparency problem.

Anyone have any ideas on what I could have done wrong? I'm stumped.

Thanks,

Rick

Hi Rick. Just so I'm clear, you're saying that you're not seeing TGA transparency inside Photoshop, right? If that's the case, there's nothing to worry about. That behavior is perfectly normal.

The reason is that alpha channels don't always have to mean transparency, and Photoshop knows that. It therefore makes no assumptions about what you might be using that fourth channel for. Most destination applications will read channel 4 in a TGA to mean transparency by default, but most source applications will not. Depending on where the image is going, that channel could mean literally anything, from transparency, to bump, to shine, to your income tax calculations, anything. SL happens to be set up to read it as transparency, but it doesn't have to be that way.

If you want to see the transparency in Photoshop, simply copy your alpha channel to a layer mask. Here's how:

1. Open your TGA file, go to the Layers Palette, and double click on the name of the background layer to turn it into a regular layer.
   
   
   
2. Go to the Channels Palette, and alt-click on the alpha channel's thumbnail to select the whole channel.
   
   
   
3. Go back to the Layers Palette, and locate the little button at the bottom that looks like a gray rectangle with a white circle in the middle. It will say "Add layer mask" when you hover your mouse over it. Click the button, and presto, you'll have your visible transparency.

Be sure to delete the layer mask before closing the file, by the way. Otherwise you risk adding a halo to your image, which is not something you want. TGA's are inherently layerless, and since masks are a function of layers, there's no way to preserve the layer mask once the file is closed.

Hello Chosen:

Thanks for the quick reply. This seems to be working perfectly. And the uploads to Sl are again transparencies instead of white backrounds.

Thank you very much. My frustration is gone.

Rick