Sky-Watcher EQ-AL55i Pro SynScan with Tripod - GoTo Equatorial Mount

Designed for astrophotography and visual observation, the Sky-Watcher EQ-AL55i Pro SynScan combines payload capacity, low weight and considerable versatility for portable astronomical configurations.

Its distinctive feature is a counterweight bar that can be installed in two different positions. This allows operation at all latitudes from 0 to 90°, including regions where conventional equatorial mounts can encounter mechanical limitations.

With a 10 kg payload capacity and a mount-head weight of only 3.8 kg, the EQ-AL55i Pro provides an attractive payload-to-weight ratio.

Control is available directly from a smartphone, tablet or computer through the built-in Wi-Fi module and free SynScan Pro application.

An illuminated polar scope is built into the mount for accurate polar alignment. USB-C, ST-4, SNAP, power and optional SynScan handset connections are also provided.

This version is supplied with a 1.75-inch stainless-steel tripod, accessory tray and a counterweight set totalling 5.3 kg.

Operation at All Latitudes from 0 to 90°

The EQ-AL55i Pro provides a latitude adjustment range of:

• 0°
• 90°

This exceptionally wide range is made possible by the counterweight bar, which can be installed in two different positions.

The mount can therefore be used both near the equator and at extreme latitudes.

10 kg Payload Capacity

Payload capacity is:

• 10 kg

This allows a wide range of optical tubes and peripheral equipment compatible with the 45 mm saddle to be installed.

Only 3.8 kg Mount Head Weight

Mount head weight is:

• 3.8 kg

Its low weight makes the mount easier to transport for field observing and astrophotography.

Built-In Wi-Fi Control

A Wi-Fi module is integrated directly into the mount.

The EQ-AL55i Pro can be controlled using the free SynScan Pro application on:

• iOS
• Android
• PC

SynScan Pro Application

The SynScan Pro application controls the mount without requiring a physical handset.

An optional SynScan hand controller can nevertheless be connected.

The optional handset provides access to a database containing more than 42,900 celestial objects, including the complete:

• Messier catalogue
• NGC catalogue
• IC catalogue

High-Precision DC Servo Motors

The EQ-AL55i Pro uses high-precision DC servo motors.

Stated right ascension axis resolution is:

• 0.32 arc-second

GoTo Speed up to 4° per Second

Maximum slewing speed is:

• 4° per second
• 1000x

This allows rapid movement between selected targets.

Astronomical Tracking

The mount provides single-axis tracking.

Available tracking rates are:

• Sidereal
• Solar
• Lunar

ST-4 Autoguider Interface

An ST-4 type autoguider interface is integrated.

Available guiding rates are:

• 0.25x
• 0.5x
• 0.75x
• 1x

Built-In Illuminated Polar Scope

A polar alignment scope is supplied with the mount.

Its integrated LED illumination assists with night-time polar alignment.

Mechanical Transmission

The right ascension axis uses a worm wheel with:

• 73.4 mm diameter
• 144 teeth

The declination axis uses a worm wheel with:

• 51.6 mm diameter
• 100 teeth

The worm drives on both axes have a diameter of:

• 11 mm

45 mm Saddle

The mount is equipped with a:

• 45 mm saddle

It accepts optical tubes fitted with a compatible dovetail bar.

Dual-Position Counterweight Bar

Counterweight bar diameter is:

• 20 mm

It can be installed in two different positions to allow operation throughout the mount's full latitude range.

Counterweights Included

A 5.3 kg counterweight set is supplied, consisting of:

• 1 × 1.8 kg counterweight
• 1 × 3.5 kg counterweight

1.75-Inch Stainless-Steel Tripod

The mount is supplied with a stainless-steel tripod.

Tripod leg diameter:

• 1.75 inch

Tripod weight:

• 5.7 kg

An accessory tray is also supplied.

Connectivity

The EQ-AL55i Pro provides:

• USB-C
• SNAP
• Power input
• ST-4
• Optional SynScan handset connection

The SNAP port allows compatible DSLR shutter control through the SynScan Pro application.

Power Requirements

The mount requires an external power supply:

• 12 V DC
• 2 A
• Centre-positive polarity

Optional Accessories

Accessories listed as available separately include:

• 200 mm tripod extension tube, product code 20860
• SynScan hand controller, product code 20948
• Hand-controller cable, product code 20193
• 5 kg counterweight, product code 20950

Technical Specifications

• Manufacturer : Sky-Watcher
• Model : EQ-AL55i Pro SynScan
• Manufacturer product code : 20859
• Type : Computerised GoTo equatorial mount
• Latitude range : 0 to 90°
• Payload capacity : 10 kg
• Mount head weight : 3.8 kg
• Wi-Fi control : Built in
• Application : SynScan Pro
• SynScan Pro compatibility : iOS, Android and PC
• Motors : High-precision DC servo motors
• R.A. axis resolution : 0.32 arc-second
• Maximum slewing speed : 4°/s
• Maximum relative speed : 1000x
• Tracking : Single axis
• Tracking rates : Sidereal, solar and lunar
• Autoguider interface : ST-4
• Guiding rates : 0.25x / 0.5x / 0.75x / 1x
• Polar scope : Included
• Polar scope illumination : LED
• R.A. worm wheel : 73.4 mm / 144 teeth
• DEC worm wheel : 51.6 mm / 100 teeth
• R.A. worm drive : 11 mm diameter
• DEC worm drive : 11 mm diameter
• Saddle : 45 mm
• Counterweight bar : 20 mm diameter
• Counterweight bar positions : 2
• Counterweights supplied : 5.3 kg total
• Counterweight distribution : 1.8 kg + 3.5 kg
• Tripod : Stainless steel
• Tripod leg diameter : 1.75 inch
• Tripod weight : 5.7 kg
• Accessory tray : Included
• USB-C connection : Yes
• SNAP port : Yes
• ST-4 port : Yes
• SynScan handset port : Yes
• SynScan handset : Optional
• Power requirement : 12 V DC / 2 A
• Polarity : Centre positive

Package Contents

• Sky-Watcher EQ-AL55i Pro SynScan mount
• Polar scope with LED illumination
• 1.75-inch stainless-steel tripod
• Accessory tray
• 1.8 kg counterweight
• 3.5 kg counterweight

Not Included

• SynScan hand controller
• 200 mm tripod extension tube
• Optional 5 kg counterweight
• External power supply