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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