OTA Sky-Watcher 250/1200 BD Black Diamond PDS Parabolic Telescope with Dual Speed Focuser
Perfect instrument for beginners and advanced very versatile
Versatile for planetary and deep sky astrophotography
Ideal for visual initiates in planetarium and deep sky
Includes 10: 1 dual speed Crayford focuser (best focus setting)
Parabolic primary mirror
Description
All about the Newton Sky-Watcher 250mm f / 5
With a 250mm primary mirror of parabolic construction, the Sky-Watcher Newton 200 collects 78% more light than a 150mm telescope. Under a very dark sky it is possible to see many objects in the sky that are barely visible on instruments of smaller diameter. It promises beginners and astronomers many years of discoveries. In planetary observation, you will reveal many details about Jupiter, Saturn and the Moon using a Barlow lens or a short focal length eyepiece.
Its Newton design offers several advantages over other families of instruments (refractors and retro-reflectors). Mirror manufacturing is cheaper for the same diameter and its medium focal length (750mm) is very versatile. You will also benefit from an attractive budget with a bright telescope that provides a diverse field of observations. The central obstruction is also lower than Cassegrain-type telescopes.
Unlike the cheaper manufacturers or small diameter Newtons, the 150, 200, 254 and 300mm Newton Sky-Watchers have a parabolic primary mirror. The mirrors are spherically polished and then re-cut to a paraboloidal shape (more expensive and difficult to obtain). It is an essential choice criterion for instruments above 130mm and short focal ratio.
Focus is obtained through a Crayford double speed eyepiece holder. Allows you to get a fine focus thanks to the 1:10 ratio. A very noticeable advantage during high magnification observations and imaging. Allows to support heavy loads (ex: APN). A 31.75mm adapter is supplied as standard to use eyepieces of the same format from the 50.8mm exit. An adjustment screw located at the bottom of the eyepiece holder maintains focus according to the orientation of the optical tube.
To present the least possible obstruction, the secondary (flat) mirror fixation bracket has 4 thin branches, 0.5 mm wide. Rigid enough, they thus limit diffraction peaks in bright stars and excessive loss of luminosity. Also standard is a 9x50 achromatic finder on its mount, as well as a 28mm (55 °) LET eyepiece for low-magnification (wide field) observations. Complete with a short focal length eyepiece for planetary observations at high magnification.
SPECIFICATIONS TUBE
Optical Design Parabolic Newtonian Reflector
Optical Diameter 250mm
Focal Length 1200mm
F/Ratio f/4.8
Highest Practical Power 500x
Faintest Steller Magnitude 14.1
Finder Scope 8 x 50
Focuser Diameter 2" with 1.25" adapter
Eyepieces LET 2"-28
Tube Weight 14.38 kg
Tube Dimensions 28.8cm x 112cm
Shipping Weight 20kg
Shipping Dimensions 127x45x56 cm3
Items delivered
1 Sky-Watcher 200mm f / 5 optical tube
1 x Crayford Sky-Watcher 50.8mm focuser with micro focuser (1:10 dual speed) and 31.75mm adapter
1 reinforced Vixen dovetail
2 clamps
1 Kodak camera overlay bracket on top of one of the mounting clips
1 x 50.8mm sliding eyepiece: LET 28mm
1 straight 9x50 finder scope