- Description
William Optics Fluorostar 91 Triplet Refractor
This beautiful 91mm f/5.9 APO triplet refractor is decked and ready to ride on your telescope mount! Whether you want to do visual astronomy, astrophotography, terrestrial observation or wildlife photography, this the scope for you! The FLT91 is designed form the optics down for a quality experience. The optics are housed in a steel lens cell and consist of three elements (triplet) made of fully multi-coated Ohara FPL-53 glass. Contrast, clarity and virtually colour-free results will boost your visual and astro-imaging to a new level.
Technical Specifications
- Lens Type
- Apochromatic Triplet Prime Lens
- Focal Length
- 540mm
- Diameter
- 91mm
- Aperture
- f/5.9
- Focuser
- Dual Speed 3.3" R&P Focuser
- Color
- Red
- Gold
- Space grey
- Lens Material
- FPL-53
- Strehl Ratio
- 0.95+
- Camera Format
- Full Frame DSLR / Mirrorless / CMOS / CCD
- Test Report
- Zygo test report available at additional cost
- T-Mounts Supported
- Canon EF, RF
- Nikon F, Z
- Sony E
- Pentax K
- Micro Four Thirds (M4/3)
- FUJI X
- Retracted Length
- 441mm
- Extended Length
- 510mm
- Extension Tube Length
- 40mm
- OTA Weight
- 4.165Kg
- Total Weight
- 5.575Kg
- Extension Tube Weight
- 0.105Kg
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