Its simple high-performance design provides tremendous light grasp at the lowest cost per unit of aperture of any type of telescope. The secondary directs the narrowed light cone out of the tube and into the eyepiece. Small Newtonians are very portable because the tube detaches from the mount in seconds. Larger Newtonians can be quite large and unwieldy, which is part of the reason more compact scope designs such as the Schmidt-Cassegrain have gained popularity. But reflectors have much to recommend them.
Optical quality can be very good.
Their large apertures make reflectors ideal for observing galaxies, star clusters, and nebulas. They also provide sharp, high-contrast planetary and lunar views. Dew does not readily form on the mirrors because the open tube acts as a passive dew shield. But because the optical tube is open to the air, it should be capped when not in use to prevent accumulation on the mirrors of dust and dirt. Reflectors are not well suited for terrestrial observing, because the image is often rotated upside-down or sideways.