The GSO 154/1848 Classic Cassegrain Binoculars Tube is the optimal choice for a high performance, yet highly portable, affordable binocular.
The long 1848mm focus, for medium to high magnifications, makes it an easy choice for eyepieces with comfortable viewing angles, but it is also a good choice for astrophotography as well as for visual purposes, for planets, the Moon, the Sun and compact deep-sky objects, although its f12 aperture makes it a better fit for more sensitive astronomical cameras. As the optics are all mirror, chromatic aberration (colour aberration) cannot be caused by the optics. Its low 33% central occlusion promises a contrasting view, enhanced by well-designed shading blends.
The tubular mirror system of the GSO 154/1848 classic Cassegrain telescope has a good light recovery, with a 94% light recovery rate, according to the manufacturer. Because the telescope tube is open at the front, it can take in ambient temperatures much faster than closed-tube catadioptric instruments. Since the GSO 154/1848 classic Cassegrain telescope tube is fixed to the main mirror, there is no image-shift mirror tilting, which is a great relief when taking photographs. Parabolic main mirrors and hyperbolic auxiliary mirrors result in less coma failure and a more contrasty image than SC telescopes.
The telescope features a 2" dual-speed Crayford focusing eyepiece for accurate, jam-free focusing. The maximum field of view available is 1.5 degrees, which is approximately 3 full moons of sky. The binoculars do not include accessories