Here's the deal. I pencil sketched a freehand cartoon for a bunch of friends and it's not simply black and white as it has some shading so there are blacks as well as several shades of gray to deal with and wispy lines as well. Also, it's on white paper, and what I'd like to do is somehow make the background yellow, or better yet... transparent so I can place it on different background colors. We're thinking we might want to have the cartoon screened onto a T-shirt. I scanned it on my Epson scanner, but there's no obvious option to make the output a transparent gif. Anyone know how to do this in Photoshop?