Celestron 200 mm Newtonian with focal ratio 1:5 A universal telescope with much power and comfort The parabolic primary of this 8" Newtonian mirror minimizes spherical aberration to produce a sharper image near the edge of the field of view. This scope is great for intermediate visual observers and beginning astroimagers looking for a large aperture with lots of light-gathering power. As the telescope is meant for users who already have a suitable mount, there is no mount included! The optics An 8" mirror collects a lot of light, increasing the perception of dim celestial objects. The relatively short focal length and the 2" focuser have a positive effect when viewing large objects, as the latter can be seen completely in the large true field of view. Because of the large focal ratio, "hard" nebula filters can be applied when using eyepieces of long focal lenght, resulting in a clearly enhanced contrast. On the other hand, the parabolic primary mirror allows high magnifications - helpful for moon, planets, planetary nebulae ans smaller galaxies. The low obstruction of only 26% gives more contrast, thus having advantages when observing planets. Of course, the fast optics has also advantages in photography, is it reduces the exposure times. The coma, typical for Newtonians, can be eliminated by a coma corrector, achieving high sharpness even in the corners of the image. General Features 8" (200 mm) f/5 optical design with 2" focuser gives excellent wide field views Parabolic primary mirror minimizes spherical aberration to produce a better image Low obstruction gives high contrast Scope of Delivery Telescope Optical Tube Assembly with rings and dovetail bar 9x50 Finderscope 1.25" Eyepiece 20 mm