Cels Forum

I believe both of these questions have been answered
on the forum before so you should try using the nifty 
search feature ^_^.

However, to save you the trouble:

I believe a pan cel is one where the camera moved 
around the image, perhaps not showing the entire  cel
at once.  It's made for a scene like when the camera
movies up someone's body so you don't see the entire
thing at once or when the scene moves along a crowd 
of people.  Hence, most pan cels tend to be oversized.

The only reference to a book cel that I have heard is that
something labeled "book" is the top layer or foreground.
However, mostly this question goes unanswered so I'm 
guessing most people don't know or aren't sure (like me.)
and that's probably why they don't want to answer your  
question. ^_^

Keys