I have one framed cel in my livingroom, which 
isn't dark at all. It's got museum grade UV glass 
and I've kept it on the shady side of the room 
where the sun never falls directly. It's been 
there for a year and has zero linefading. (I 
check, lots.. I worry about my baby!) The cel 
itself is 10 years old, and still looks pristine.

I have heard tho that the UV glass should be 
replaced every 2-3 years, which I will def be 
doing.

Cheers,
-Heather