Powerful telescopes

"long-range" telescopes

— "Long-range" telescopes designed to observe distant ("deep-space") objects like nebulae, double stars, etc. The key requirements for such observations are high magnification and good resolution. Both require the use of large diameter lenses — at least 200 mm; in fact, this can only be realized when using a lens in the form of a mirror, therefore, among the "deep-space" telescopes, only reflectors and mirror-lens models are presented.