Assertion: reflecting telescope's mirror | /r/HasProperty | expensive to produce
Facets:
Source sentences:
text: Newtonian reflectors will have either a spherical shaped mirror, which is less expensive to produce, or a higher quality parabola, which does not result in spherical aberration.
text: Because a mirror is less expensive to make than a complex group of lenses reflectors offer the biggest 'bang for the buck' in terms of aperture and as a result are much favored by amateurs especially for deep sky observing of galaxies and nebula.
text: Newtonian reflectors will have either a spherical shaped mirror, which is less expensive to produce, or a higher quality parabola, which does not result in spherical aberration.