Takahashi FSQ-80FC 80mm f/5.6 Quintuplet Astrograph Refractor OTA

Product Overview

The FSQ-80FC is Takahashi's compact 80 mm imaging refractor, built around a 5-element optical design with dual fluorite elements. At a native 450 mm focal length and f/5.6, it is intended as a wide-field astrograph rather than a visual scope — the flat field and 50 mm image circle cover a full-frame sensor without a separate flattener. Takahashi lists a tube weight of approximately 4.1 kg.

Who It's For

This is a good match if you want a wide-field, grab-and-go imaging refractor that travels light — the compact tube and roughly 4.1 kg weight suit a smaller equatorial mount or a travel setup, and the flat 50 mm image circle covers full-frame sensors without an accessory flattener to buy separately.

Key Features & Design

• 5-element optical design with dual fluorite elements: corrects chromatic aberration and field curvature within the tube, without a separate corrector.
• 450 mm focal length at f/5.6: a fast, wide field of view suited to nebulae, star clusters and large-scale mosaic targets.
• 50 mm image circle: covers full-frame sensors with a flat field, as published by Takahashi.
• Native M48 interface with 55 mm back focus: supports direct camera attachment with minimal adapter stacking, reducing flexure in the imaging train.
• Retracting dew shield: tube length runs 486 mm retracted to 559 mm extended for storage and transport.
• Rack-and-pinion focuser: holds a full imaging train of camera, filter wheel and guider.

Optical / Mechanical Design

The FSQ-80FC carries Takahashi's quintuplet Petzval-derived design — five elements including two fluorite lenses — aimed at flattening the field and correcting color across the frame without a separate flattener accessory. At f/5.6 and 450 mm focal length it trades focal length for field width and speed, the combination astrographs are built around. The aluminum tube and fully multi-coated optics are typical of the FSQ line's imaging-first design; where Takahashi's other refractors are sold as visual-capable OTAs with an optional flattener, the FSQ-80FC's flattening is built into the base optical prescription.

Recommended Uses

Wide-field deep-sky astrophotography of nebulae, large star clusters and galaxy fields; full-frame mosaic imaging; travel and portable imaging rigs where tube weight and length matter.

Compatibility and Accessory Notes

Takahashi publishes a 55 mm back focus from the native M48 interface, which is enough to seat most cooled cameras directly or with a thin adapter stack — filter wheels and off-axis guiders add up quickly against that figure, so it is worth checking your full imaging train before ordering.

Good to Know Before You Order

Published weight is approximate: Takahashi's own listing states "approx. 4.1 kg" rather than an exact figure.

Mount and tripod are not included: this listing is the optical tube assembly only.

Frequently Asked Questions

Is it difficult to set up?

No — the flattening is built into the optics, so there is no separate corrector to thread on and space out. The M48 interface accepts a camera directly once your adapter stack is sorted.

What is it best used for?

Wide-field deep-sky astrophotography where a fast, short-focal-length refractor covers more sky per frame than a longer telescope.

Can I use it for visual observing?

It is built and marketed as an imaging astrograph; its native interface and back focus are set for a camera, not an eyepiece.

What cameras does it fit?

Any camera that reaches the 55 mm back focus through the M48 interface, including full-frame cooled CMOS and CCD cameras — send us your camera and filter setup and we will work it out with you.

How is this different from the FSQ-85EDX?

They are separate optical designs, each on its own specification sheet — figures for one do not describe the other.

Bottom Line

In short: a compact 80 mm f/5.6 quintuplet astrograph with a built-in flattener, a 50 mm image circle, and roughly 4.1 kg of travel-friendly weight, built for wide-field imaging over visual use.