Sky-Watcher Esprit 120EDX Apochromatic Refractor

Designed primarily for demanding astro-imagers, the Sky-Watcher Esprit 120EDX is a 120 mm three-element Super APO apochromatic refractor with an 840 mm focal length and f/7 focal ratio.

Its optical system retains the f/7 configuration of the previous generation and incorporates a Japanese Ohara FPL-53 ED glass element. This optical design provides a high level of chromatic correction, with detailed, high-contrast images and no detectable colour fringing even on very bright objects.

Every air-to-glass surface of the objective features Metallic High-Transmission Coatings MHTC. Stated light transmission approaches 99.5%, helping to optimise the amount of light passing through the optical system.

The rear mechanical assembly has been redesigned for easier astrophotography use. The capstan wheel used on the previous model has been removed, allowing the focuser itself to rotate more easily. An additional rotatable adapter fitted directly to the drawtube provides precise control over camera orientation and image framing.

Focusing is provided by a CNC-machined hybrid rack-and-pinion Linear Power focuser with 11:1 reduction, a 3-inch indexed drawtube, high accessory load capacity and stated zero image shift.

The optical tube is supplied with CNC-machined aluminium tube rings, a top accessory rail that also serves as a carrying handle, and a 75 mm dovetail mounting bar. The complete assembly is supplied in a foam-lined aluminium-framed storage and carrying case.

Ohara FPL-53 Super APO Triplet

The 120 mm objective uses a three-element apochromatic design incorporating a Japanese Ohara FPL-53 ED glass element.

This optical configuration provides a very high level of chromatic correction, with no detectable colour fringing even on the brightest objects.

The system provides high contrast and sharpness for demanding astronomical imaging as well as visual observation.

840 mm Focal Length at f/7

With a focal length of 840 mm and an aperture of 120 mm, the Esprit 120EDX operates at f/7.

This configuration provides a useful balance between field of view, resolution and light gathering for astrophotography.

Its 120 mm aperture also provides strong performance for visual observation.

MHTC Coatings

Every air-to-glass surface of the triplet objective features Metallic High-Transmission Coatings MHTC.

These metallic anti-reflection coatings are designed to optimise light transmission through the optical system.

Stated light transmission approaches 99.5%.

CNC Dual-Speed Linear Power Focuser

Focusing is provided by a CNC-machined hybrid rack-and-pinion Linear Power focuser.

Its dual-speed 11:1 reduction combines rapid coarse focusing with highly precise fine adjustment for imaging.

The focuser offers high accessory load capacity for supporting photographic equipment.

Image shift during focusing is stated to be zero.

3-Inch Indexed Drawtube

The focuser incorporates a 3-inch indexed drawtube.

The scale helps identify and reproduce a previously determined focus position.

A drawtube adapter is also supplied to accept a 2-inch star diagonal.

Dual Rotation System

The Esprit 120EDX provides two independent rotation options.

The focuser itself can be rotated separately.

An additional adapter fitted to the drawtube provides full 360° rotation.

This arrangement allows precise camera orientation and image framing without changing the position of the optical tube on the mount.

Optional Field Flattener

A dedicated field flattener is available separately for the Esprit 120EDX under product code 20189.

With the optional field flattener, the stated image height is 44 mm.

The field flattener is not supplied with the telescope.

Optional 0.77× Reducer/Flattener

A 0.77× reducer/flattener is also available separately under product code 20095.

This accessory is intended for imaging applications with the Esprit 120EDX.

It is not supplied with the telescope.

Retractable Dew Shield

The Esprit 120EDX features a retractable dew shield.

The optical tube measures 710 mm with the dew shield retracted and 810 mm when extended.

This design reduces the overall size of the telescope for transport and storage.

Aluminium Optical Tube with Internal Baffling

The optical tube is manufactured from aluminium.

Internal baffling is incorporated to reduce unwanted reflections within the optical tube and preserve contrast.

CNC Tube Rings and Accessory Rail

The optical tube is supplied with CNC-machined aluminium tube rings.

A top accessory rail is integrated into the assembly and also serves as a carrying handle.

This arrangement facilitates handling and provides an additional mounting point for compatible accessories.

75 mm Dovetail Bar

A 75 mm dovetail mounting bar is supplied.

It provides the mounting interface for a compatible astronomical mount.

Finderscope Mounting Shoe

A finderscope mounting shoe is installed on the telescope.

It is compatible with Sky-Watcher finderscopes.

Aluminium Carrying Case

The Esprit 120EDX is supplied in an aluminium-framed storage and carrying case.

The interior is foam lined to protect and secure the telescope during transport and storage.

Visual Observation

Although the Esprit EDX range is designed primarily for demanding astrophotography, the Esprit 120EDX is also well suited to visual observation.

The drawtube adapter accepts a 2-inch star diagonal.

Technical Specifications

• Manufacturer : Sky-Watcher
• Model : Esprit 120EDX
• Product code : 10300
• Type : Super APO apochromatic refractor
• Optical design : ED triplet
• Objective diameter : 120 mm
• ED glass : Ohara FPL-53
• Number of lens elements : 3
• Focal length : 840 mm
• Focal ratio : f/7
• Optical coating : Metallic High-Transmission Coatings MHTC
• Stated light transmission : Approaching 99.5%
• Focuser : Hybrid rack-and-pinion Linear Power
• Focuser construction : CNC machined
• Focuser : Dual speed
• Reduction ratio : 11:1
• Focuser drawtube diameter : 3 inch
• Drawtube : Indexed
• Focuser accessory capacity : High load capacity
• Image shift : Stated zero
• Focuser rotation : Yes, independently rotatable
• Drawtube adapter rotation : 360°
• Star diagonal adapter : 2 inch
• Finderscope mounting shoe : Compatible with Sky-Watcher finderscopes
• Dew shield : Retractable
• Optical tube : Aluminium
• Internal baffling : Yes
• Tube rings : CNC-machined aluminium
• Top accessory rail / carrying handle : Included
• Dovetail mounting bar : 75 mm
• Tube length with dew shield retracted : 710 mm
• Tube length with dew shield extended : 810 mm
• Optical tube weight : 10.84 kg
• Dedicated field flattener : Available separately
• Optional field flattener product code : 20189
• Image height with optional field flattener : 44 mm
• Reducer/flattener : 0.77× available separately
• Optional reducer/flattener product code : 20095
• Carrying case : Aluminium framed and foam lined

Package Contents

• Sky-Watcher Esprit 120EDX optical tube
• CNC-machined aluminium tube rings
• Top accessory rail / carrying handle
• 75 mm dovetail mounting bar
• 2-inch star diagonal adapter
• Finderscope mounting shoe
• Foam-lined aluminium-framed carrying case

Not Included

• Eyepiece
• Star diagonal
• Finderscope
• Optional field flattener 20189
• Optional 0.77× reducer/flattener 20095