Question On TGA Files & Alpha Channels

C
Posted By
Crash
Jan 9, 2004
Views
495
Replies
6
Status
Closed
I recently started using PS to add alpha channels to images for use as texture maps in 3D graphics applications. After adding the desired alpha channel I save the image as a 32 bit Targa file. Then I bring it into my 3D ap. and use the alpha information to make different parts of an object transparent, opaque, or somewhere in between. This all works great. No problem so far.

BUT – when I bring the Targa image back into PS, the alpha channel is gone? When I bring up the channels pallette, only RGB channels show. What’s up with that? Where did it go? Apparently the alpha info is still in the file, because the 3D transparency stuff still works. What am I missing here?

Thanks.

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MR
Mike Russell
Jan 9, 2004
Crash wrote:
I recently started using PS to add alpha channels to images for use as texture maps in 3D graphics applications. After adding the desired alpha channel I save the image as a 32 bit Targa file. Then I bring it into my 3D ap. and use the alpha information to make different parts of an object transparent, opaque, or somewhere in between. This all works great. No problem so far.

BUT – when I bring the Targa image back into PS, the alpha channel is gone? When I bring up the channels pallette, only RGB channels show. What’s up with that? Where did it go? Apparently the alpha info is still in the file, because the 3D transparency stuff still works. What am I missing here?
When you open the image, are you looking at the channels palette, or the layers palette?

The layers palette comes up by default, and may create the impression that the alpha channel has gone away.


Mike Russell
www.curvemeister.com
www.geigy.2y.net
E
edjh
Jan 9, 2004
Crash wrote:
I recently started using PS to add alpha channels to images for use as texture maps in 3D graphics applications. After adding the desired alpha channel I save the image as a 32 bit Targa file. Then I bring it into my 3D ap. and use the alpha information to make different parts of an object transparent, opaque, or somewhere in between. This all works great. No problem so far.

BUT – when I bring the Targa image back into PS, the alpha channel is gone? When I bring up the channels pallette, only RGB channels show. What’s up with that? Where did it go? Apparently the alpha info is still in the file, because the 3D transparency stuff still works. What am I missing here?

Thanks.
I bet you are using Photoshop 7.0. Update to 7.0.1 which fixes this.


Comic book sketches and artwork:
http://www.sover.net/~hannigan/edjh.html
C
Crash
Jan 10, 2004
You are correct. I went to the Adobe website and read all about the targa problem in 7.0. I probably should have done this before posting my question! So the solution for me is either to download 7.0.1 or the targa plug-in to 7.0. Thanks for the tip.

"edjh" wrote in message
Crash wrote:
I recently started using PS to add alpha channels to images for use as texture maps in 3D graphics applications. After adding the desired
alpha
channel I save the image as a 32 bit Targa file. Then I bring it into
my 3D
ap. and use the alpha information to make different parts of an object transparent, opaque, or somewhere in between. This all works great. No problem so far.

BUT – when I bring the Targa image back into PS, the alpha channel is
gone?
When I bring up the channels pallette, only RGB channels show. What’s
up
with that? Where did it go? Apparently the alpha info is still in the file, because the 3D transparency stuff still works. What am I missing here?

Thanks.
I bet you are using Photoshop 7.0. Update to 7.0.1 which fixes this.

Comic book sketches and artwork:
http://www.sover.net/~hannigan/edjh.html
R
Robert
Jan 10, 2004
Just wanted to drop you a line and say I remember your stories and art – Great Stuff – Thanks

Why aren’t you doing more, if I may ask?

On Fri, 09 Jan 2004 22:25:56 GMT, edjh posted:
"Re: Question On TGA Files & Alpha Channels"

Crash wrote:
I recently started using PS to add alpha channels to images for use as texture maps in 3D graphics applications. After adding the desired alpha channel I save the image as a 32 bit Targa file. Then I bring it into my 3D ap. and use the alpha information to make different parts of an object transparent, opaque, or somewhere in between. This all works great. No problem so far.

BUT – when I bring the Targa image back into PS, the alpha channel is gone? When I bring up the channels pallette, only RGB channels show. What’s up with that? Where did it go? Apparently the alpha info is still in the file, because the 3D transparency stuff still works. What am I missing here?

Thanks.
I bet you are using Photoshop 7.0. Update to 7.0.1 which fixes this.
E
edjh
Jan 10, 2004
Robert wrote:
Just wanted to drop you a line and say I remember your stories and art – Great Stuff – Thanks

Why aren’t you doing more, if I may ask?

Thanks

The comics industry sort of imploded in the late 90s and (like many) I had a difficult time finding work. It’s rebounded somewhat but I have moved on and so has comics. I am doing some pieces which will soon be posted for sale on my website. I’ve done some private commissions but finding the time to do them has been a problem.


Comic book sketches and artwork:
http://www.sover.net/~hannigan/edjh.html
R
Robert
Jan 10, 2004
On Sat, 10 Jan 2004 12:45:53 GMT, edjh posted:
"Re: Attn: edjh – Re: Question On TGA Files & Alpha Channels"

Robert wrote:
Just wanted to drop you a line and say I remember your stories and art – Great Stuff – Thanks

Why aren’t you doing more, if I may ask?

Thanks

The comics industry sort of imploded in the late 90s and (like many) I had a difficult time finding work. It’s rebounded somewhat but I have moved on and so has comics. I am doing some pieces which will soon be posted for sale on my website. I’ve done some private commissions but finding the time to do them has been a problem.

Thanks for the reply and thanks for the help and advice you’ve given in this newsgroup. I’ll check with your site from time to time.

How to Master Sharpening in Photoshop

Give your photos a professional finish with sharpening in Photoshop. Learn to enhance details, create contrast, and prepare your images for print, web, and social media.

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