This instrument represents a large-aperture, collapsible Dobsonian telescope designed for visual observation of celestial objects. Its defining feature is a truss-tube design, allowing for a significantly reduced storage size when not in use. The ‘400p’ designation indicates a primary mirror diameter of 400mm (approximately 16 inches), providing substantial light-gathering capability. As a Dobsonian, it utilizes a simple, alt-azimuth mount, prioritizing ease of use and affordability for amateur astronomers.
The primary advantage of this type of telescope lies in its large aperture. Larger apertures collect more light, enabling the observation of fainter and more distant objects, such as nebulae, galaxies, and star clusters. The collapsible design addresses the challenge of portability often associated with large telescopes. Traditionally, large-aperture instruments were cumbersome and difficult to transport. The truss-tube system allows the optical tube assembly to be disassembled, making it considerably more manageable for transport to dark-sky locations away from urban light pollution. The Dobsonian mount, invented by John Dobson, further contributes to its accessibility by offering a stable and intuitive platform without the complexity and expense of computerized equatorial mounts.