Many of us remember the blue tube Coulter Optical Dobsonian telescopes, the first of which contained a 13.1-inch primary mirror. Soon, amateur telescope makers and companies began producing larger ...

Orion’s SkyQuest XX16g GoTo Truss Tube Dobsonian Telescope has an f/4.4 focal ratio. It comes with a 2″ dual-speed Crayford focuser, 28mm and 12.5mm eyepieces, and a 42,000-object database.