William Optics FLT Fluorostar 91 with Ultra Flat 0.79x used

William Optics FLT Fluorostar 91 with Ultra Flat 0.79x used

Description

This used bundle combines the William Optics FLT Fluorostar 91 apochromatic refractor with the Ultra Flat 0.79x reducer, providing a complete solution for wide field astrophotography. The FLT Fluorostar 91 features a triplet APO optical design enabling correction of chromatic aberrations and precise detail across the entire field.

With a focal length of 540 mm and a focal ratio of f 5.9, this refractor offers a balance between brightness and resolution. Its 43 mm image circle allows full frame sensor coverage while remaining compatible with APS C and Micro 4 3 formats. The 3.3 inch rack and pinion focuser, compatible with motorized focus systems, provides 95 mm of travel ensuring precision and stability.

The tube includes M92 rotator, M92 extender and M92 to 2 inch RotoLock adapters, allowing direct integration into various setups. The Vixen type dovetail ensures compatibility with many mounts.

The included Ultra Flat 91 0.79x reducer reduces focal length and increases field of view while maintaining field correction. It features a 4 element optical group with an optical length of 105.5 mm. It connects via M83 telescope thread and M54 camera thread, ensuring compatibility with APS C and full frame sensors.

This bundle is offered in very good used condition. The combined new value is 2680 CHF VAT included and it is offered at 1600 CHF VAT included.

Technical specifications

• Manufacturer: William Optics
• Model: FLT Fluorostar 91
• Type: apochromatic triplet refractor
• Focal length: 540 mm
• Aperture: 91 mm
• Focal ratio: f 5.9
• Image circle: 43 mm
• Focuser: 3.3 inch rack and pinion compatible EAF
• Focuser travel: 95 mm
• Included adapters: M92 rotator M92 extender M92 to 2 inch RotoLock
• Optional flatteners: FLAT68III 1.0x FLAT6AIII 0.8x Ultra Flat 91 0.79x
• Sensor formats: full frame APS C Micro 4 3
• Dovetail: Vixen
• Tube length: 441 mm to 510 mm
• OTA weight: 4.16 kg
• Total weight: 5.57 kg
• Included product: Ultra Flat 91 0.79x reducer
• Reduction factor: 0.79x
• Optical design: 1 group 4 elements
• Optical length: 105.5 mm
• Telescope thread: M83 x 1 x 6 mm
• Camera thread: M54 x 0.75 x 4 mm
• Compatible formats: APS C full frame
• Weight: 1140 g
• Condition: very good used
• New total value: 2680 CHF VAT included
• Selling price: 1600 CHF VAT included