• Caption: The primary (M1) and tertiary (M3) mirrors (for the Large Synoptic Survey Telescope) were cast as a single 8.4-m blank. The inner part will become a 5-m f/0.8 tertiary mirror, while the outer part 5.0 to 8.4-m diameter will be an f/1.25 primary mirror
  • Aperture: ƒ/4
  • Shutter Speed: 1/60
  • Date: 2/11/11 4:10:58 PM MST