I guess we should factor in the viewers eyesite, the older I get the more trouble I have getting the bifocals just right to view a print on the wall or in my hands...
Making rather small prints, 4x5, 5x7, 4x10 and 8x10, paid off money wise a few years back when a local bank purchased 18 to display in small areas of their banks. One never knows....
Wm Blunt

Guess that doesn't have a lot to do with lampshades, sorry!