Dobsonian telescopes offer an incredible aperture-to-price ratio. The Dobsonian mount, popularized by John Dobson in the 1970.s, is a simple and efficient method of mounting a Newtonian reflector, based on the alt-azimuth principal. Fast and easy to set up, the Dobsonian mount consists of a box-type mounting which allows the telescope to pivot in altitude, while the box itself is rotated on a base in azimuth. The secret of the design is to correctly balance the optical tube and use frictional materials which allow it to be moved easily when nudged but to stay in position when not. The mount is designed to be driven by hand as opposed to slow motion controls. Sky-Watcher Dobsonians provide excellent all round performance for the observation the moon and planets and deep-sky objects such as galaxies and nebulae.

The Skyliner-250PX has a "paraboloidal" primary mirror to eliminate spherical aberration and a four-arm, secondary- mirror bracket with fine supports (0.5mm thick), to reduce diffraction spikes and light loss. The mirror is made from Pyrex, a material which offers less thermal expansion and therefore faster cool-down times compared to float glass.

Characteristics:

• Aperture 254mm, focal lenght 1200mm, f/4.8
• Central obstruction appr. 27%
• 2" focuser with reduction 1¼"
• Resolving power: 0.45"
• Total weight appr. 32kgs

Delivery:

• 10" Dobsonian Telescope
• 2" focuser with reduction 1¼"
• 9x50 finder with dovetail connector
• 25mm & 10mm 1¼" Super eyepieces