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Baader Planetarium 31mm Hyperion Aspheric Modular Hyperion Eyepiece - HYP-31

Baader Planetarium 31mm Hyperion Aspheric Modular Hyperion Eyepiece - HYP-31 - Main image
$137.86 $226 In stock

Category: Telescope Eyepieces

This Baader Planetarium 31mm Hyperion-Aspheric modular eyepiece is the world’s first astronomical eyepiece to use aspheric surfaces.  This new technology eliminates eyepiece aberrations without the usual penalty of extra lens elements, excessive size and weight, or high cost.  

Two barrel sizes are included with this innovative eyepiece, allowing you the flexibility of using it in both 1.25 inch and 2 inch focusers.  The standard 2” barrel displays the full 72 degree field of view, and the special wide-field 1.25 inch barrel provides the maximum true field ever in a 1.25 inch format, with a field stop size of 32mm!

Long eye relief for extreme comfort while viewing

The Baader Hyperion Aspheric eyepiece offers freedom from blackouts, kidney beaning, and lack of distortion.   The design also provides long eye relief, and produces a view that is uncommonly comfortable and natural for all users—even eyeglass wears and those who like to use devices that correct for astigmatism.

72 degree flat field of view

The ultra-wide 72° field of this Hyperion-Aspheric is extremely flat and distortionless.  It is virtually free of angular magnification distortion, providing you with unparalleled views of the Universe.  Phantom Group Multi-Coatings are applied to the optics to increase transmission and contrast, and thorough internal baffling keeps light from scattering.

 Baader Hyperion-Aspheric eyepieces are perfect for projection imaging

The Hyperion-Aspherics are threaded to accept the full line of Hyperion Digital T-Rings, for a robust direct attachment of almost any camera.  The clever use of 2 inch x 24 tpi SCT threads on the eyepiece body allows either this Hyperion-Aspheric to be threaded directly onto the rear cell of popular Schmidt-Cassegrain telescopes.  This results in the highest rigidity possible for imaging, and makes for one of the most flexible eyepieces on the market today.

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Customer Reviews (4.8 / 5 · 5 reviews)

Grace ★★★★★

The 31mm focal length with that wide field makes sweeping the Milky Way feel effortless, and the aspheric design keeps stars sharp right to the edge. I’ve spent hours on the Moon and double stars without any of the usual edge distortion I’ve fought with in other eyepieces.

Isabella F. ★★★★★

The aspheric glass really does clean up the edges—stars stay pin-sharp right to the field stop, which I wasn't expecting at this price. It's become my go-to for sweeping the Milky Way, and the modular barrel lets me pop it into my 2" diagonal without a single adapter.

Riley X. ★★★★★

I've spent hours on the Moon and M42 with this, and the field is so flat and sharp that stars stay pinpoints even near the edge—no more refocusing or constant fiddling. The modular twist-lock mechanism feels solid, and swapping the top section for my 2" adapter took seconds, which is a huge plus in