Hello all:
 
How big should prints be in a photographic exhibit?  Are there any general rules?  The prints we are using are made from 5x7 glass plate negatives dating from 1858 to 1884.  I have suggested we go with 11x14 (originally we thought 8x10 but they are really small on the wall).  What do you think about blowing them up to 16x20 (this is what our photographer has suggested)?
 
FYI: the gallery is 1320 square feet but we only have 124 linear feet of hanging space.  The ceiling is 18 feet high, but the walls have a hanging surface of only 7 feet four inches.
 
Thanks for your advice,
Rebecca J. Phipps