Sky-Watcher Esprit EDX 120 mm F/7 Optical Tube Assembly OTA (SW-2035)

Sky-Watcher Esprit EDX 120 mm F/7 Optical Tube Assembly (SW-2035)

The Esprit 120 EDX represents the latest generation of one of the most highly regarded astrographs in the prestigious Esprit series. It is a premium-class apochromatic triplet refractor with an optional screw-in field flattener, designed primarily for demanding astrophotography. As the successor to the very popular Esprit 120, the EDX version retains its outstanding optical performance while introducing significant mechanical improvements that enhance stability and usability with modern imaging setups.

The optical system consists of three precisely matched elements. One lens is made from Japanese Ohara FPL-53 low-dispersion glass, while the remaining elements are crafted from Schott glass. This configuration virtually eliminates chromatic aberration and significantly reduces spherical aberration and astigmatism across the entire field of view. As a result, the telescope produces exceptionally sharp, high-contrast star images without color fringing or distortion, even when imaging large areas of the sky. Despite its f/7 focal ratio, the telescope remains free from typical off-axis aberrations such as distortion and astigmatism.

Esprit Series Overview

The Esprit series includes apochromatic refractors with the following configurations:

• 70 mm F/7

• 80 mm F/5

• 100 mm F/5.5

• 120 mm F/7

• 150 mm F/7

These telescopes are designed as advanced astrographs for demanding users, but they also perform exceptionally well for high-end visual observations. They offer excellent contrast, high resolution, and a wide, perfectly corrected field of view. This makes them ideal for imaging nebulae, galaxies, and star clusters, as well as observing the Moon and planets.

Key Improvements in the EDX Version

The EDX version introduces several important upgrades compared to the earlier Esprit 120 model:

• New CNC-machined 3-inch Linear Power rack and pinion focuser

• 11:1 microfocuser for extremely precise focusing

• Integrated 360° rotator for easier framing in astrophotography

• Increased load capacity for heavy cameras, filter wheels, and accessories

• Improved rear tube construction for greater overall stability

• Enhanced compatibility with full-frame and large-format sensors

Advanced Focuser System

The telescope is equipped with a modern 3-inch Linear Power rack and pinion focuser, manufactured using CNC technology. This design ensures exceptional rigidity and smooth, precise focusing thanks to the 11:1 microfocuser. The focuser includes an indexed scale on the drawtube and a built-in rotator that allows full 360° camera rotation, making framing much easier during imaging sessions. Included adapters support both threaded 3"/2" connections and 2"/1.25" compression fittings.

Astrophotography Performance

With a focal length of 840 mm and a focal ratio of F/7, the Esprit 120 EDX is a highly capable astrograph offering a large, flat image field and perfectly corrected stars across the entire frame. A dedicated optional field flattener ensures consistent sharpness all the way to the edges of the sensor, providing an image circle of approximately 44 mm, suitable even for full-frame cameras. A backfocus of around 75 mm and the 3-inch focuser allow comfortable use with complex imaging setups.

High-quality multi-layer MHTC anti-reflection coatings ensure excellent light transmission, while an advanced internal baffling system effectively suppresses stray light and enhances contrast. The combination of outstanding optics, robust mechanical construction, and a modern focuser system makes the Esprit 120 EDX one of the most advanced astrophotography telescopes in its class.

Included Accessories

• 75 mm dovetail bar

• Tube rings

• Aluminum carrying case

Technical Specifications

• Catalog number: SW-2035

• Optical design: Refractor

• Objective lens material: FPL53

• Mount type: Not included

• Aperture: 120 mm

• Focal length: 840 mm

• Focal ratio: f/7.0

• Limiting magnitude: 13.0

• Maximum useful magnification: 240x

• Resolution (Rayleigh): 1.19 arcseconds

• Resolution (Dawes): 0.97 arcseconds

• Light gathering power: 294x

• Optical tube weight: 10.9 kg

• Tube length: 710 mm

• Focuser type: Rack and pinion

• Focuser diameter: 3 inches

• Microfocus adjustment: Yes

• Mounting rail: Losmandy standard

• Warranty: 60 months