Hey, congratulations! That is great! IMHO, I stick with what you know and use the highest quality JPEG images possible. Then save it as a Photoshop file as soon as you start working with it. A big project like this is no time to start learning new tricks. Maybe after you finished with it you can play... Backdrops like that are not printed at a very high resolution and will look fine blown up. I just had a trade show booth printed up and the resolution they use is 120 dpi. Can I assume you may be "stiching" some photos together to create the backdrop? Have fun!

Kort Kramer - Kramer Kreations