The Sky-Watcher Flextube 300P Collapsible Dobsonian Optical Tube Assembly gives users great performance at a reasonable price. Its large parabolic borosilicate primary mirror is treated with a combination of quartz, titanium, and silicon dioxide that brings its reflectivity to 94%, with a secondary mirror obstruction of just 5% by area. Unlike traditional Dobsonians that tend to be bulky and unwieldy, the Flextube's patented truss design allows it to retract to just 36" for easier transport and storage, and then extends to 55" for observation.
The large 12" aperture draws in copious amounts of light to resolve deep-sky objects like wispy nebulae and galaxies, while also revealing incredible details of the lunar surface and planetary features. Included are 10 and 25mm 1.25" eyepieces, but the focuser comes with an adapter allowing 2" eyepieces to be used.
- Large 12" aperture is able to resolve dim deep-space objects like wispy nebulae and galaxies
- Fast f/4.9 focal ratio ensures a wide field of view, maximum light throughput
- Long 1500mm focal length helps to produce fast focal ratio and moderate magnification potential
- Collapsible truss system saves space during transport and storage, measuring just 36" when trusses are retracted and extending to 55" when set up
- Borosilicate parabolic primary mirror
- Quartz, titanium, and silicon dioxide mirror coatings bring the reflectivity to 94%
- Resolution: 0.38 arcsec (Dawes Limit), 0.46 arcsec (Rayleigh Limit)
- 70mm secondary diameter mirror; Obstruction: 23% by diameter, 5% by area
- 55.5" eyepiece height when aimed directly overhead at the zenith
- 14.25" (23.81cm) outside tube diameter