Sky-Watcher Quattro 250P Imaging Newtonian 10" (254 mm)

Sky-Watcher Quattro 250P Imaging Newtonian 10" (254 mm) Sky-Watcher SKU: S11220 | Helix SKU: CTS11220 Overview The new Sky-Watcher Quattro Imaging Newtonian with dual-speed focuser incorporates a superb mirror-set with two significant advantages over competing products. A 2" dual-speed 10:1 ratio focuser is included for excellent focusing precision. Additionally, the tube length has been slightly shortened to optimize performance for prime-focus photography Specifications:  SKU S11220 UPC 050234112208 Optical Info Optical Design Newtonian Mirror Coatings 94% Aluminum Glass Type Borosilicate True Aperture (mm) 257 Primary Aperture (mm) 254 F/Ratio 4 Focal Length (mm) 1000 Secondary Diameter 89mm Secondary Obstruction (by diameter) 35% Secondary Obstruction by Area 12% Observational Info Dawes Limit 0.46 Rayleigh Limit 0.55 Limiting Mag. 14.5 Minimum Magnification 36 Maximum Magnification 500 Light Gathering (compared to next si