Product Description: These Folded 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 Black ^TM low reflectivity surface coating), these telescopes offer exceptionally high image contrast. The 10-in. Alpha Draconis Folded 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. Folding flat first surface mirrors of 8-in. and 6-in diameters are placed so as to reduce the overall length of the tube assembly to approximately 1/3 that of the Alpha Draconis 10-in. standard OTA. The OTA structure consists of a fully enclosed rectangular truss tube with extensive internal stray light baffling. 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.

10-in. Alpha Draconis Achromatic OTA: $41,250, FOB Pinecliffe, Colorado USA. Completion within 5 months of receipt of order. An initial deposit of 50% is required with the order.

10-in. Alpha Draconis Apochromatic OTA: $99,600, FOB Pinecliffe, Colorado USA. Completion within 12 months of receipt of order. An initial deposit of 50% is required with the order.