Astro Systeme America’s ASA800 is the largest aperture OTA. At 0.08 meters, the ASA800 is an f/6.85 full carbon fiber truss Richey-Chrétien design with an absolute encoder secondary mirror focusing unit.

The telescope’s quartz glass optics have ultra low micro-roughness to limit diffraction even under the best atmospheric conditions, and the primary mirror with its fast f-ratio is designed for minimal obstruction and high contrast.

• Optical Design: Ritchey-Chrétien (RC)
• Central Obstruction: 41%
• Focal Length: 5,480 mm
• Focal Ratio: f/6.85
• Clear Aperture / Focal Ratio Primary Mirror: 800 mm (31.5 inch) / f/2.5
• Image Field: 120 mm (1.25 degrees)
• Mirror Material: Fused Silica
• Surface Quality: >94 Strehl
• Micro-roughness: 1nm RMS / <0.7nm Ra
• Coating: Al+SiO2 >96%
• Back Focus from Flange: 345.73 mm
• Tube Weight: 542 lb. (246 kg)