The Size of the Sky
The area of the whole sky is approximately 41,250 square degrees.
The Hubble Space Telescope's ACS camera takes images that are 3.4' x 3.4 ' (0.0032° x 0.0032°).
The HST has so far taken several hundred thousand images. At its current image capture rate, it would take the HST around two thousand years to completely photograph the sky.
Location of images taken with the HST
Most large telescopes have a similar field of view to the HST.