Description

Introducing the William Optics FLT91, a precision-engineered apochromatic triplet refractor designed for discerning astronomers and astrophotographers. This mid-sized telescope features a 91mm aperture with FPL-53 glass, delivering sharp, high-contrast images and an impressive Strehl ratio exceeding 0.95.

Equipped with user-centric features, the FLT91 includes an integrated saddle handle, a 360º field rotator, a dual-speed 3.3" Rack & Pinion focuser, and a 2" Rotolock system. These enhance usability and provide stability for both visual and photographic applications.

Astrophotographers will find the built-in Bahtinov mask invaluable for achieving perfect focus effortlessly. Compatible with the Flat6A III and Flat68 III, the FLT91 allows precise back-focus adjustments.

Constructed with William Optics' signature quality, the FLT91 is both lightweight and durable, weighing 4.2 kg and 5.6 kg fully equipped. It comes with a soft carry case for easy transportation and protection.

Ideal for capturing celestial phenomena, the William Optics FLT91 is a top choice for those seeking advanced optical performance in a portable package.

Specifications

Lens Type: Triplet Apochromatic Prime Lens
Focal Length: 540mm
Diameter: 91mm
Aperture: f/5.9
Image Circle: 63mm
Focuser: 3.3" R&P Focuser, compatible with EAF
Adapter Included: M92 Rotator, M92 -> 2" RotoLock
Optional Flattener: FLAT68III 1.0x (requires adapter), FLAT6AIII 0.8x (requires adapter)
Camera Format: Full Frame, APS-C, M4/3
Tube Length: 441mm - 510mm
OTA Weight: 4.16kg / 9.17lbs
Total Weight: 5.57kg / 12.28lbs