Fluorostar 91
New for 2021 -
The FLT 91 is the perfect Apochromatic refractor for visual and photographic astronomers demanding excellence in a midsize telescope. The three-element optical design features a 91mm aperture using FPL-53 glass. The STM-coatings and superb quality provide excellent optical performance and unmatched value.

RotoLock
The Rotolock 2 inch adapter provides for a solid and efficient connection for a WO 2 inch diagonal, and other accessories.

Bahtinov Mask
Patented
The retractable dew shield features a removable lens cover, with our patented Bahtinov Mask revealed
by
unscrewing the face plate. The clear design allows for brighter star patterns, and precise focusing
for
astrophotography.
The retractable dew shield features a removable lens cover, with our patented Bahtinov Mask revealed by unscrewing the face plate. The clear design allows for brighter star patterns, and precise focusing for astrophotography.
Versatile Saddle Bar
Patented
The Saddle Bar Handle, offers a solid handle with a built in dovetail chamber for use with the WO Uniguide scopes, or other Vixen style guiding/finder scopes.


New Focuser Knob
A larger fit designed for better ergonomics.
Field Rotator
The super smooth field rotator includes markings for every degree, and a solid thumbscrew position lock.


Soft Carry Case
The standard package comes with a soft carry case.
Technical Specifications
- Lens Type
- Apochromatic Triplet Prime Lens
- Focal Length
- 540mm
- Diameter
- 91mm
- Aperture
- f/5.9
- Flattener
- FLAT 6A III x0.8
- FLAT 68 III x1.0
- Flattener Adjustment
- FLAT 6A III x0.8: 5.4mm
- 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
Optional Accessories
UNIGUIDE 32/120MM

FLAT 6A III 0.8x
Focal length: 432mm

What's in the Box

Fluorostar 91

Vixen Saddle Plate

Visual Extension Tube

Soft Carry Case

Handle Bar
