Baader Hyperion Aspheric 72° 36mm Eyepiece - 1.25"/2"

Aspheric Optics and Phantom Coatings: A Brighter 72° Field

Unlike traditional eyepieces that use multiple spherical lenses to control aberrations, the Hyperion Aspheric 36mm employs aspheric surfaces to achieve sharp, high-contrast views across the entire field with fewer glass elements. This simplified optical path, combined with Baader's 7-layer Phantom Group multi-coatings, maximizes light throughput and minimizes internal reflections.

The result is a brighter image that reveals fainter stars and more delicate nebulosity compared to more complex wide-field designs. The coatings are optimized for the human eye's peak sensitivity, ensuring neutral color rendition and preventing the light loss associated with lower-quality green-reflex coatings.

The 72° AFOV: Full Immersion Without Eye Strain

Baader deliberately engineered the Hyperion Aspheric with a 72° apparent field of view. This angle is wide enough for an immersive experience yet allows you to take in the entire starfield at once without straining or "rolling" your eye to see the edges.

Many ultra-wide eyepieces suffer from a "nervous" view, where slight movements of your eye cause the image to black out. The Hyperion Aspheric provides a stable, comfortable, and forgiving eye position, making it an excellent choice for extended observing sessions and for sharing views at public outreach events.

Mechanical Design: 1.25"/2" Barrels, SCT Threads, and Imaging Ports

The Hyperion Aspheric 36mm is built for flexibility. It features a dual-format barrel that fits directly into both 1.25" and 2" focusers without adapters, making it compatible with virtually any telescope.

• Direct SCT Connection: The eyepiece body includes a 2" Schmidt-Cassegrain thread, allowing you to screw it directly onto the rear cell of an SCT. This creates a rigid connection and can provide a wider true field than using a standard 2" diagonal and nosepiece.
• Imaging-Ready: An M43 thread on the eye lens side and compatibility with the SP 54 system allow for the direct attachment of DSLR and other cameras for high-resolution afocal imaging.
• Binoviewer Compatible: Its design is compact enough to be used in most binoviewers, a rare capability for a long-focal-length 2" wide-field eyepiece.

Hyperion 36mm Aspheric vs. 80°+ Ultra-Wide Eyepieces: A Deliberate Trade-Off

While eyepieces with 80° or wider apparent fields offer a more expansive "spacewalk" view, this often comes at a cost. To achieve such a wide field with spherical lenses requires complex, multi-element designs that can dim the image and reduce contrast.

The Hyperion Aspheric 36mm prioritizes image brightness and sharpness over raw field size. Observers consistently report that the Aspheric reveals finer stars and fainter structures in nebulae than more expensive ultra-wide eyepieces. It represents a conscious design choice: a fully usable 72° field with superior light transmission is often more effective than a larger, dimmer field where the edges are hard to see.