Takahashi Extender-QE 1.6x 2" Field Flattener for FSQ-106EDX4

Product Overview

The Extender-QE 1.6x is the five-element 2-inch extender built specifically for Takahashi's current FSQ-106EDX4 ("New Q") refractor, also published for the FSQ-130ED. It brings the FSQ-106EDX4's native 530mm f/5.0 up to 850mm f/8.0 while holding a flat, colour-corrected 44mm image circle, and doubles as a high-magnification visual accessory.

Who It's For

This is a good match if you own an FSQ-106EDX4 or FSQ-130ED and want tighter framing on small deep-sky targets than the astrograph's native wide field delivers, or higher-power lunar and planetary views without switching telescopes.

Key Features & Design

• Five-element optical design: delivers a flat, colour-corrected, high-contrast image at the extended focal length rather than a simple magnifier.
• 1.6x extension: 530mm f/5.0 becomes 850mm f/8.0 on the FSQ-106EDX4.
• 44mm image circle held constant at the extended focal length.
• Secure mounting features: an anti-slip groove and dual thumbscrews keep the extender seated through the imaging or visual session.
• Fully multi-coated optics for high-contrast imaging and visual use alike.

Optical / Mechanical Design

Built for the FSQ-106EDX4's New Q focuser, the Extender-QE 1.6x uses a five-element design rather than a simple Barlow doublet, which is why the image circle stays a corrected 44mm at the extended 850mm f/8.0 rather than degrading toward the edges the way a plain magnifier would. Takahashi also publishes the same part for the FSQ-130ED, where it extends 650mm f/5.0 to 1040mm f/8.0.

Recommended Uses

Tighter deep-sky framing on the FSQ-106EDX4 or FSQ-130ED, plus higher-magnification lunar and planetary visual observing without short-eye-relief eyepieces.

Compatibility and Accessory Notes

Takahashi publishes this extender for two current telescopes.

This is the part for the current FSQ-106EDX4; the earlier fluorite FSQ-106 and Sky-90 use the separate Extender-Q 1.6x, also carried by Ontario Telescope. For spacing your full imaging train, see the Takahashi Back Focus Guide.

Good to Know Before You Order

Not the same part as the original Extender-Q: the earlier fluorite FSQ-106 and Sky-90 need the separate Extender-Q 1.6x rather than this one.

Frequently Asked Questions

Is it difficult to set up?

No — it seats into the 2-inch focuser with an anti-slip groove and dual thumbscrews, and the 117.5mm back focus is fixed by the unit.

What is it best used for?

Tighter deep-sky framing and higher-power lunar/planetary imaging on the FSQ-106EDX4 or FSQ-130ED.

Will this fit an older fluorite FSQ-106?

No — that telescope uses the separate Extender-Q 1.6x. Send us your FSQ-106's markings if you are not certain which generation you have and we will confirm the right part.

Does it work for visual observing as well as imaging?

Yes — it functions as a high-magnification visual accessory in addition to a photographic extender.

Bottom Line

The Extender-QE 1.6x extends the FSQ-106EDX4 to 850mm at f/8.0 with a flat, colour-corrected 44mm image circle, and does the same for the FSQ-130ED at 1040mm f/8.0.