Starfield Gear90 (EDT90) — 90mm f/6 Triplet APO Refractor with FPL-53

The Starfield EDT90 f/6 Triplet APO (Gear Series) is a compact refractor platform built for wide-field astrophotography while remaining capable as a high-magnification visual instrument. The optical system uses FPL-53 ED glass in a triplet APO objective, paired with Gear Series standard hardware: heavy-duty rings, a Vixen-style dovetail, and an accessory-ready handle.

For imaging workflows, the Gear90 integrates a Camera Angle Adjuster (CAA) to support framing without introducing flex or forcing changes to focuser position, and it includes a 2.5" two-speed rack-and-pinion focuser with a retractable dew shield.

Why the Gear90 (EDT90) Works for Wide-Field Imaging

Triplet APO optics with FPL-53 ED glass

The objective is specified as a multicoated APO triplet using FPL-53. This configuration is intended to support wide-field imaging and strong color correction for demanding targets.

Optional reducer and flattener for a threaded, rigid imaging train

The Gear90 supports an optional 0.8× adjustable reducer and an optional 1.0× flattener. These are described as threaded for a secure connection to the focuser with no flex, helping maintain alignment across heavier camera loads.

The page also shows a field-of-view comparison graphic stating that the Gear 90 with 0.8× reducer provides a larger field of view than an Esprit100, with the Gear90 shown in red.

Focuser, Rotation, and Framing

2.5" two-speed rack-and-pinion focuser (ball-bearing supported)

The telescope includes a 2.5" two-speed rack-and-pinion focuser with ball bearings and full rotation. The design is presented as supporting heavy cameras and accessories, and optional motor focusers can be installed.

63mm / M63x1 accessory interface and pressure-fit lock

The focuser is described as accepting 63mm accessories and includes an M63x1 female thread. A pressure-fit lock is specified for securing the imaging train.

Camera Angle Adjuster (CAA)

The integrated CAA is intended to make it easy to frame targets while keeping the imaging train rigid and maintaining focuser position.

Mechanical Package and Handling

Rings, dovetail, and handle for transport and accessory mounting

Gear Series standard hardware includes HD CNC tube rings, a Vixen-style dovetail bar, and a handle designed for transport and accessory mounting. The handle is specified as supporting Vixen and Arca-Swiss accessories.

Retractable dew shield

A retractable dew shield is included for compact transport. The specifications note it can be fixed with one screw.

Visual Observing Capability

High magnification claim (as stated on the page)

The page states that, when used visually, the Gear90 can reach magnifications up to 300× with no chromatic aberration. (As with any refractor, actual usable magnification depends on seeing conditions, thermal stability, and optical alignment.)

What’s Included

• Hard case with die-cut foam
• Optical test report
• HD CNC tube rings
• Vixen-style dovetail bar
• Accessory/transport handle
• Retractable dew shield

Technical Specifications (EDT90 / Gear90)

• Aperture: 90 mm
• Focal length: 540 mm
• Focal ratio: f/6
• Objective: Multicoated APO triplet lens — FPL-53
• Limiting magnitude: 12.3 mag
• Resolution: 1.29"
• Weight (tube alone): 9 lbs
• Weight (with rings, dovetail bar, and handle): 12 lbs
• Dew shield: Retractable (can be fixed with one screw)
• Focuser: 2.5" CNC focuser; connections include 2", 1.25", and M63x1 female thread
• Microfocuser: 1:10 ratio fine-focus knob
• Finder interface: Standard finder shoe
• 2" adaptor: Brass compression ring with 3 clamping screws
• Tube: Internally baffled to suppress stray light and improve contrast

Gear90 FAQ

Is the Gear90 intended for imaging loads?

Yes—the page emphasizes the 2.5" two-speed rack-and-pinion focuser with ball bearings, full rotation, and support for heavy cameras/accessories, plus a CAA for framing without adding flex.

What reducers/flatteners are available?

An optional 0.8× adjustable reducer and an optional 1.0× flattener are listed, described as threaded for a secure connection to the focuser with no flex.

What is the telescope’s focal length?

540 mm at f/6.