If you are using Poser5 - suggest using PNG format - and using background color as that is how I create my animation characters into sprites for FlashMX and DirectorMX... Png format was only one that was happy in creating sprites with no background (not photoshop). If I need to take it to Illustrator - I use the middle man Image Ready. Then I can cut out the background in Illustrator. The PNG format also works (transparent wise) with Jasc PaintshopPro and the Animator program that comes with it.