SkyWatcher Esprit 80EDX APO OTA

The Sky-Watcher 80mm Esprit 80EDX Triplet APO Refractor is a professional instrument for the most demanding and exacting astro-photographers. The air spaced apochromatic triplet lenses use the remarkable Ohara FPL-53 ED (extra low dispersion) glass, with exceptional colour correction over the entire visible spectrum there is no chromatic aberration even on bright objects! Knife edge baffles reduce internal reflections and increase contrast, helping to bring out faint structure in deep sky objects. A 2-element field flattener is included to iron out the natural off-axis astigmatism and field curvature of the objective lens, leaving a fully corrected 42mm field of view. The Sky-Watcher exclusive Helinear Track 11:1 dual speed focuser is rock solid with zero image shift and a 3″ barrel to avoid vignetting. Designed with photography in mind, it sits on two tracks above and below the barrel to prevent flexure with a heavy camera attached, and is fully rotatable to perfectly frame a target on the sensor. In The Box: 80/400 Apochromatic Refractor Rotatable focuser adapter Collapsible Dew Shield Field Flattener with M48 Thread T2 Canon Camera Adapter 2″ Dielectric Star Diagonal 9×50 Right Angled Erect Image Diagonal D Style dovetail Bar 2″ to 1.25″ Eyepiece Adaptor Aluminium Foam-Lined Case Model SWESPRIT80EDX Optical Design Airspaced Apochromatic Triplet Aperture 80 Focal Length 400mm Focal Ratio f/5 Diameter of the corrected field 33mm Visual Back Focus 160mm Resolving Power 1.50″ Stellar Limit Magnitude 11.8 Highest Practical Magnification 160X Light gathering power (compared to the unaided eye) 131 Focuser 2.7″ Crayford dual speed with 2″ and 1.25″ adaptor Optical Tube Length0 Optical Tube Weight 3.97kg