William Optics Fluorostar 91 FPL53 Triplet APO Refractor with 3.3" Rack & Pinion Focuser - Gold

William Optics Fluorostar 91 Triplet APO Refractor Telescope with 3.3" Rack & Pinion Focuser - Gold Version

With a 3-element triplet design and FPL-53 glass, this William Optics 91 mm f/5.9 FLT Apochromatic Refractor is just the excellent midsized visual and photographic instrument sought by discerning astronomers. Compared to similar telescopes currently on the market, the Fluorostar 91 offers unrivaled optical performance and value thanks to STM coatings.

RotoLock Adapter

A dependably effective 2" William Optics diagonal or accessory to FLT91 connection is provided by the RotoLock 2" adapter.

Bahtinov Mask

The face plate on the retractable dew shield's lens cover can be removed to expose the William Optics patented Bahtinov Mask. With the clear design of this Mask, you'll enjoy more luminous star patterns as well as precision focusing for astro-imaging.

Versatile Saddle Bar

The Saddle Bar, in addition to its solid handle, contains a built-in dovetail chamber for attaching the William Optics Uniguide or other V series guiding and finder scopes.

New Focuser Knob

A larger design makes the focuser knob more ergonomic and easy to use.

Field Rotator

This exceptionally smooth field rotator with solid thumbscrew position lock contains markings for every degree.

Soft Carry Case

A soft carry case comes standard with the William Optics Fluorostar 91.

William Optics Fluorostar 91 Triplet APO Refractor Technical Specifications

• Lens Type: Apochromatic Triplet Prime Lens

• Focal Length: 540 mm

• Aperture: 91 mm

• Focal Ratio: f/5.9

• Focuser: Dual-Speed 3.3" Rack & Pinion

• Color: Gold

• Lens Material: FPL-53

• Strehl Ratio: 0.95+

• Camera Format: Full Frame DSLR/Mirrorless/CMOS/CCD

• Supported T-Mounts: Canon EF, RF/Nikon F, Z/Sony E/Pentax K/Micro Four Thirds (M4/3)/Fuji X

• Retracted Length: 441 mm

• Extended Length: 510 mm

• Extension Tube Length: 40 mm

• OTA Weight: 9.2 lbs. (4.165 kg)

• Total Weight: 12.3 lbs. (5.575 kg)