Fluorostar 91
Category: Refractor Telescope
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
The mount pictured in images is not included.
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When it ships
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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.
Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.
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Standard Shipping · United States: $0.00
Express Shipping · United States: $3.99
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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.
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