Fluorostar 91
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The EQ Mount in the images is not included.
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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.
- Lens Type
- Apochromatic Triplet Prime Lens
- Focal Length
- 540 mm
- Diameter
- 91 mm
- Aperture
- f/5.9
- Image circle
- 46 mm
- Focuser
- Dual Speed 3.3" R&P Focuser
- Optional Flattener
- FLAT68III 1.0x (requires adapter)
- FLAT6AIII 0.8x (requires adapter)
- Adapters
- N/A
- Lens Material
- FPL-53
- Camera Format
- > Full Frame
- T-Mounts Supported
- Canon EF, RF
- Nikon F, Z
- Sony E
- Pentax K
- MFT (M4/3)
- FUJI X
- Tube Length
- 441 mm - 510 mm
- OTA Weight
- 4.17 kg / 9.18 lbs
- Total Weight
- 5.58 kg / 12.29 lbs
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