Alpha Draconis 10 Inch Refractor OTAs
These Optical Tube Assemblies provide both high resolution imaging performance and the good light grasp of a 10 inch aperture. Because the tubes are fully enclosed and fitted with internal light baffles (coated with our proprietary Deep Sky BlackTM low reflectivity surface coating), these telescopes offer exceptionally high image contrast.
The 10-in. Alpha Draconis OTA is offered in Standard Achromatic and Full Apochromatic versions. All optical elements are fabricated from precision annealed Schott Grade A optical glass blanks and are hand figured by laser autocollimation testing against a NIST certified optical flat mirror in our own USA facilities. Both versions incorporate fully adjustable objective cell assemblies, 2-stage coarse/fine focussers with squaring-on adjustments and a 120 mm aperture refractor finder/guide telescope.
The OTA structure consists of a center section mated to flanged objective and tailpiece tube sections. The objective lens is shielded by a baffled dewcap/lightshade extension tube. An adjustable longitudinal trim weight is provided for fine balance compensation of focal plane accessories.
Objectives: 10 inch (250mm) Fraunhofer achromat or 5 element apochromat
Focal ratio: F12 focal length 120 inches (3048mm)
Tube diameter: 12 inches (305mm)
Overall length: 136 inches (3454mm)
Focusing: 8 inch (200mm) rack and pinion draw tube with capstan screw fine focus
Eyepieces: 2/1.25 inch
Weight: 268 pounds (122 kilos)
Achromat: from $41,250 ex-works
Apochromat: from $99,600 ex-works
Imports to UK attract approximately 6.5% import duty and 20% VAT plus shipping