Tecnosky 90/540 F6 APO Refractor Triplet FPL55 OWL Series (Ref. TKASLD90O)

Tecnosky 90/540 F6 APO Refractor Triplet FPL55 OWL Series (Ref. TKASLD90O)

Description:
The Tecnosky 90/540 F6 OWL is a premium apochromatic refractor built around a triplet lens made of Ohara FPL55 glass, combined with high-index elements and FMC anti-reflective coatings. Each scope comes with an interferometric certificate showing a Strehl ratio of at least 0.95, confirming its exceptional optical quality.

The black-anodized CNC-machined aluminum tube includes internal baffles for stray light suppression. The retractable dew shield locks in place, and the mechanics are designed for both visual and astrophotographic use. The 2.5" rack-and-pinion focuser offers 1:10 fine focus and includes a field rotator and both 2"–1.25" and 2"–31.8 mm adapters. A graduated scale is printed on the focuser tube for repeatable setup.

The CNC rings with handle and Vixen-style dovetail bar make mounting easy. A custom hard case is included.

Technical specifications:

• Objective: air-spaced triplet, central lens made of Ohara FPL55

• Coatings: FMC on all optical surfaces

• Certified Strehl ratio: ≥ 0.95 (interferometric test included)

• Focal length: 540 mm

• Aperture: 90 mm

• F-ratio: F/6

• Focuser: 2.5" rack and pinion with field rotator, 1:10 micrometric knob

• Adapters: 2" to 1.25" and 2" to 31.8 mm

• CNC rings with Vixen-type dovetail bar and carrying handle

• Retractable dew shield with lock

• Retracted length: 480 mm, extended: 520 mm

• Weight: 4890 g (with rings and dovetail)

• Supplied with rigid padded hard case

Additional information:
The scope is compatible with full frame sensors at native F/6, and with the optional Tecnosky 0.8x reducer it becomes a fast F/4.8 astrograph. A versatile instrument combining mechanical quality and high-end optics.