Product Overview
Designed with the discerning astrophotographer in mind, Sky-Watcher USA’s top-of-the-line Esprit refractors deliver the kind of imaging performance one would expect from telescopes costing thousands of dollars more.
With their three-element air spaced objective lens design, false color is completely eliminated, yielding exceptional contrast and sharpness. The included 2-element field corrector guarantees a flat field across the entire imaging plane. The Sky-Watcher exclusive Helinear Track focusing system provides a smooth, rock-solid focuser with zero image shift.
All Sky-Watcher USA Esprit refractors come with a 8 x 50 right angle finderscope, 2-inch Star diagonal, 2-element field flattener*, camera adapter, D-style dovetail and padded case. Everything you need to get out under the stars.
Specifications
Optical Design | ED Triplet |
---|---|
Primary Aperture (mm) | 80mm (3?) |
Focal Ratio | 5 |
Focal Length (mm) | 400mm |
Glass Type | Schott/Ohara ED |
Lens Coatings | Fully Multi-Coated |
OTA Length | 17.4? |
OTA Outer Diameter | 4.875? |
OTA Weight (with accessories) | 8.8 lbs. |
Focuser | 2.7? Dual Speed R&P |
Included Eyepieces | None |
Included Diagonal | 2? Dielectric |
Included Finder | 8×50 Right Angle Correct Image |
Includes Case | Yes |
Mounting Accessories | V-Rail Foot |
Corrector | Yes, included flattener. |
Image Circle (w/ Flattener) | 33mm |
Other Included Items | Canon 48mm camera adapter with spacers |
Dawes Limit | 1.45 |
Rayleigh Limit | 1.75 |
Limiting Magnitude | 12 |