- Sky-Watcher ED Refractor, without Mount
- Diameter 120mm (4.75″)
- Focal Length 900mm
- F/Ratio F/7.5
- Finder Scope 8×50
- Focuser Diameter 2″ dual speed, crayford
- Diagonal 2″ 90 deg. Dielectric Diagonal with 1.25 inch adapter
- Eye Piece LET 2″-28mm
- Tube Weight 5.16 Kgs
- Tube Dimensions 10cm x 62cm
Metallic High-Transmission Lens Coatings
Each air-to-glass lens surface has exotic anti-reflection metallic coatings applied to ensure optimum light through-put of approaching 99.5%. The proprietary Sky-Watcher “Metallic High-Transmission Coatings” (MHC) are the finest photon anti-rejection coatings in their class.
Light-Baffled Optical Systems
The objective lens cell is light-baffled to reject stray, unfocused light. The draw tube is likewise baffled to insure optimum contrast. The tube interior is flat blackened to help prevent unfocused internal light reflections from reaching the focal plane.
Precision 2” Dual Speed Crayford Focuser is Standard
Optical focus is achieved by means of a mechanically ultra-smooth, backlash-free, precision 2” Dual Speed Crayford Focuser-assembly. This focuser offers fine and ultra-fine focusing adjustments.
The optical tube material is rolled steel, powder-coated reflective gloss black with gold fleck accent. The front and back cells are cast-aluminum painted white, or black.
Telescope Tube Attachment Hardware:
The optical tube comes with attachment hardware that allows it to be securely fastened to any Sky-Watcher mount. The quick-release tube rings provided with Black Diamond 80 ED are cast-aluminium, painted white.
Black Diamond 80 ED is supplied with 2” Dual Speed Crayford Focusers and quality foam-lined aluminium carrying cases as standard equipment.