CS2 Targa Problem?

Is anyone else having a problem with transparancies in the new Photoshop CS2 with the targa format?

Every other version of PS saves the tga with a transparent background when you save it as a 32bit, but this new CS2 saves it as a white background

Please help if you can it's driving me nuts!

See this thread: /109/8b/48537/1.html for a fix.

Personally I've been finding that having to make my own alpha channel (go to the channels pallet and click the new button if you don't have one) has been really quite informative and often easier or more useful. I guess that depends on what you're making though.

Actually every other version of Photoshop behaved exactly the way CS2 does, with the sole exception of Photoshop 7.0, which was Adobe's one and only experiment with automatic alpha channel creation. The experiment was a dismal failure, as it offered almost no control over the final look of the image, and was very prone to artifacts such as the all too familiar white halo of doom that plagues so many images in SL. Acknowledging this failure, Adobe patched it very quickly with 7.0.1.

With respect, I STRONGLY recommend against doing what the above mentioned link says. If you have Photosho CS2, or any version of Photoshop other than 7.0, leave it exactly as is. If you have 7.0, get the free 7.0.1 patch from adobe.com. DO NOT change your TGA save process file to act like that of 7.0. Photoshop 7.0 was Adobe's one and only attempt at automated alpha channel creation for TGA images, and it didn't work. It was an idea that sounded really good in concept, but turned out to be really, really, really bad in practice. All it did was eliminate the level of control that manual channel editing allows, and it made every single image prone to the white halo effect without any way to get rid of it. Here's an exerpt from a previous thread where I talked abut this in some detail:



There are numerous threads on this board about TGA transparency, so you can take comfort that you're not alone in asking. In fact, it's the single most commonly asked question on the whole of the forums. Here's my standard 10 step tutorial on how to create them, preceded by an explanation of what they are. I've pasted this tutorial into many threads on this forum, and just about everyone has found it helpful. My girlfriend was able to follow it, and she'd never previously used Photoshop in her life so I know it's fool proof.

Color Space & Channels
Images designed to be shown on a color screen are comprised three colors (red, green, & blue). The relative brightness of each of these primary colors in each pixel determines each pixel's actual color. For example, a pixel comprised of equal values of red and blue without any green would appear to be purple.

When taken seperately, the individual values for red, green, or blue are represented by a grayscale image called a channel. In an individual channel, white represents the maximum possible concentration of color and black represents the absense of color. Shades of gray represent amounts of color that are less than the maximum. The darker the gray, the lesser the concentration of color. The lighter the gray, the more color is present.

Channels & Transparency (Alpha Channels)
Images that have transparency have the same three primary color channels and also have a fourth channel, called Alpha, which represents opacity. In the alpha channel, white represents comlete opacity and black represents the absense of opacity (transparency). Shades of gray represent semi-transparency. The darker the gray, the more transparent. The lighter the gray, the more opaque.

So, for example, if you are making a bikini top for your avatar, the alpha channel would be white in the shape of the bikini top, and black everywhere else. The white part makes the bikini top 100% opaque so that you won't be able to see through it when it's on the av, and the black part makes the rest of the image invisible so that there appears to be nothing on the av's arms, stomach, etc.

How to Create an Alpha Channel
Let's stick with the example of a bikini top.

1. On the Layers Palette turn off all layers except for the layer that has your bikini on it. (To turn a layer off, click the eyeball symbol to the left of its name.)

2. If the bikini layer has any white space around the bikini itself, use the eraser to get rid of the white space. It's very important at this stage that the bikini be on its own layer with nothing else on it.

3. On the Layers Palette, ctrl-click the icon for the layer with the bikini on it. (The icon is the little picture of the layer directly to the left of the layer's name.) This will select everything on the layer. You should see the "marching ants" outlining your bikini now.


4. On the Layers Palette, click the tab that says Channels to switch it to the Channels Palette. What you should see listed here are the three primary channels for your image, labled, "Red", "Green", & "Blue", and a master channel for the three, labelled "RGB". If you see any other channels besides those four, delete them now.

5. In the lower right corner of the Palette Window, locate the button that looks like a square sticker being peeled from its backing. It's the second one from the right. It's immediately to the left of the one that looks like a trash can. It says "New Channel" when you hover your mouse over it. Click it.

6. You should now see a new layer called "Alpha 1", which is currently all black. Make sure all channels except for Alpha 1 are turned off and that Alpha 1 is turned on. This should have happened automatically when you created Alpha 1, but if it didn't, do it now.

7. Your canvas should now appear to be solid black with the exception that you should still be able to see the "marching ants" outline of your bikini. Paint everything inside the outline white and leave everything outside of it black.

8. Click "Select" on the menu bar at the top of the screen to pull down the Select Menu. Click "Deselect" and you should see the marching ants disappear.

9. On the Channels Palette, trun the red, green, & blue channels back on, and turn Alpha 1 off. Now click the tab that says layers to switch back to the Layers Palette. Create a new layer by pressing the same button you previously used to create the new channel. (Just as it created a new channel while you were on the Channels Palette, it will create a new layer while you're on the Layers Palette.) Click on the name of this new layer and drag it underneath the layer with the bikini on it. Paint the new layer 50% gray or darker; black is fine. (The gray/black layer will prevent the white halo sometimes caused when Alphas are created the way we just did it. If you don't know what I mean by that, don't worry about. Just make sure to always put a gray/black layer underneath your work and you'll never have to see that white halo.)

10. Save your file as a 32-bit TGA and upload it to SL.

You might also want to look at my video tutorial, which uses CS2 to make an Alpha channel (without any white halos, I might add.)

If you already have the transparency, though, don't use the Magic Wand to select the pixels for the mask; hold down command/ctrl, and click on the thumbnail in the Layers palette to select the non-transparent pixels instead. It's far more accurate, and will correctly interpret semi-transparent pixels.

I'll try to get a video of that technique up later today.

Welcome back, Robin. Sounds like you're feeling better. Good to hear.

Thanks everyone for the help!

Thanks, Chosen!

Yeah; I won't be really back until November, (family emergency, which means I have to travel to New Jersey,) but I'm putting my two cents in when I can.

Unfortunately, I didn't get the tutorial done, and now it looks like I won't have time to do it until sometime after I return. As they say, if it's not one thing, it's another.

Thank you Robin for the video. This has turned out to be the best explanation of how to make crisp high quality alpha channels I have seen on the forum. I hope you will be making more (basic T-shirt anyone?!)! Great stuff! Cheers!

I'm glad you found it helpful, Spinderella!

There's a plan for a t-shirt tutorial in the works, but it might be a few weeks. I'll post when I have it done. (Or, rather, when I have them done, since it's going to have to be more than one to put all the information I want to squeeze in there in there. )

That would be awesome.. I was able to get rid of all seams and the white halo from this shirt by following your tutorials. But I am having trouble getting my seams to line up. No matter how percise I am in following Chip's seam guide.. They are always a little bit off.

This shirt has been recreated 12 times and the results are always the same. :/