...will it decrease the value of my cel? I have a 
few cels that have some serious line fading, and 
I was wondering if I were to repair the lines 
directly on the cel itself, would that decrease 
the value of the cel? 

I trust myself to do it directly on the cel (I am 
an artist...I sure hope I have a steady hand, or 
else I'd be in trouble), but I'm wondering if I 
should do it on a separate sheet of acetate, just 
to preserve the value of the cel...

any help would be greatly appreciated! (I tried 
searching the forum archives about this but it 
kept giving me an internal server error!)