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) | 100mm (4") |
| Focal Ratio | 5.5 |
| Focal Length (mm) | 550mm |
| Glass Type | Schott/Ohara ED |
| Lens Coatings | Fully Multi-Coated |
| OTA Length | Dew Shield Retracted: 18.3? Dew Shield Extended: 24.5? |
| OTA Outer Diameter | 5.75? |
| OTA Weight (with accessories) | 16 lbs. |
| Focuser | 3.4" Dual Speed R&P |
| Included Eyepieces | None |
| Included Diagonal | 2" Dielectric |
| Included Finder | 8×50 Right Angle Correct Image |
| Includes Case | Yes |
| Mounting Accessories | Rings/D-Rail |
| Corrector | Yes, included field flattener. |
| Image Circle (w/ Flattener) | 40mm |
| Other Included Items | Canon 48mm camera adapter with spacers |
| Dawes Limit | 1.16 |
| Rayleigh Limit | 1.4 |
| Limiting Magnitude | 12.5 |
