Other uses are in imaging systems such as monoculars, binoculars, telescopes, microscopes, cameras and projectors. In settings near astronomical telescopes and observatories, low pressure sodium lamps may be used. Mounts used for Telescopes, microscopes and generic optics. Nearly all large research-grade astronomical telescopes are reflectors. Almost all of the major telescopes used in astronomy research are reflectors. This is the mechanism used by telescopes, binoculars and light microscopes. It is the practice of observing celestial objects by using telescopes and other astronomical apparatus. Images are typically created by devices such as cameras, mirrors, lenses, telescopes, microscopes, etc. This applies to monoculars, binoculars and telescopes. Corona Borealis contains few galaxies observable with amateur telescopes. Examples of some of the largest achromatic refracting telescopes, over diameter. For psychedelic drugs are simply instruments, like microscopes, telescopes, and telephones. All refracting telescopes use the same principles. Observations are usually performed using networks of robotic telescopes. These were used for low noise microwave receivers in radio telescopes and satellite ground stations.