[Leon]

Using Photoshop

Create a new file. Make sure that it is a "legal" pixel size
and that it uses "RGB" color mode. "Contents"
can be white or transparent and it can be any resolution,
although 72 pixels/inch is recommended.
In the Layers window, create a New Layer. (Click and hold
the right-pointing arrow on the upper-right corner of the
Layers window for a menu.)
In the new Layer, create your detail, whether by painting
from scratch or pasting in an image you've copied from
elsewhere.
When you are done painting your detail, go to the menu and
choose "Select," and "All" to select the entire image in
your new layer. Then "Edit" and "Copy" from the menu (or
CTRL+C) to copy the entire image.
In the Layers window, select the "Channels" tab (or on the
menu, "Windows," "Show Channels").
Create a New Channel (use the same arrow menu as for New
Layer). Accept the defaults for the name and "masked areas."
A new Alpha channel will appear in your Channels window; by
default it will be black and current.
On the top menu, select "Edit," and "Paste." This will paste
a grayed version of your detail on top of the black alpha
channel.
Make white (RGB: 255, 255, 255) your current color. With the
pasted selection still active, select from the top menu
"Edit" and "Fill," and use "foreground color" (which should
be white).
You might want to double check that your Alpha layer is
aligned with your RGB layers -- "Paste" is not always
accurate. Make both channels visible and moved the entire
alpha channel as needed.
If you want parts of your detail to blend in with the
background paint on the the Building Architect building
(i.e., semi-transparent), then use a gray color in the alpha
channel instead of white. The darker the gray, the more the
background will show through.
Under "File," select "Save a Copy..." Save the file in Targa
(.tga) .You should save it at 32
bits/pixel.
Leon

leonmohpa@yahoo.com
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