Compactness can be achieved today with the advent of the
u4/3rds system as lenses can be mounted very close to the
sensor. A C-mount lens that just covers a 4/3rds sensor
size is compared to a standard 35mm film lens. Today,
lenses tend to be bulky in size because of the use of
plastic barrels that need to be thicker than metal, the
use of internal focus motors and desire for longer zoom ranges.