Takahashi FCT-65D fluorite apochromatic triplet refractor OTA version

Takahashi FCT-65D fluorite apochromatic triplet refractor OTA version

A state-of-the-art, robust, compact and lightweight optical telescope developed for the modern era of digital astrophotography!

Takahashi FCT-65D fluorite triplet apochromatic refracting telescope OTA-only version. Diameter D=65 mm, focal length f=400 mm (F/6.2). Includes camera angle adjuster (CAA), 2" eyepiece holder and reduction to 1.25" with self-centring ring. Original rings and Vixen/GP-stule dovetail available separately.

The optics consists of an apochromatic triplet with a calcium fluorite (CaF2) crystal central lens. The optical design allows a polychromatic Strehl ratio of 97.5 per cent on axis and excellent containment of longitudinal spherical aberration.

The Takahashi FCT-65D apochromatic refractor features a native focal length of 400mm and a focal ratio of F/6.2. Takahashi will also soon release a specially designed, high-performance focal reducer for this instrument called  65D FU Reducer 0.65x that screws directly into the focuser body. Using the dedicated focal reducer, the Takahashi FCT-65D apochromatic refractor becomes a high-performance wide-field astrograph with only 260 mm focal length and a very fast focal ratio of F/4 with very high correction even on the 24x36 mm full frame format! Stellar diameters remain confined to within 2-3 microns RMS radius. Illumination at the edge of the full-frame format reaches an excellent 70%.

The Takahashi FCT-65D apochromatic refractor is also compatible with the Takahashi Multi-Flattener 1.04x, with a resulting focal length of 416 mm and focal ratio of F/6.4.

As can be seen from the diagrams, we highly recommend the dedicated 65D FU Focal Reducer 0.65x for maximum performance. Being a dedicated optical design, the overall correction is superior.

Accessories and equipment

A high-precision CAA camera rotator is part of the instrument's standard equipment. A set of aluminium rings with an inner diameter of 95 mm (TKA11420) and a Vixen/GP type dovetail plate (TKA11423) are also available as separate accessories.

A 2" eyepiece holder and the classic system of reduction rings up to the 1.25" self-centring eyepiece holder typical of Takahashi are also part of the standard equipment.

The tube is oversized in the centre section and near the focuser (95 mm diameter) to accommodate the high-performance 65D FU Focal Reducer.

Technical Specifications

• Aperture: 65 mm
• Focal length: 400 mm
• Focal ratio: F/6.2
• Optical tube length: 399 mm
• Optical tube diameter: 95 mm (OTA is oversized to fit dedicated focal reducer)
• Lens hood diameter: 80 mm
• Weight of optical tube only: 1.9 kg
• Photo visual system chart Takahashi FCT-65D

Takahashi FCT-65D presentation video and other upcoming Takahashi telescopes