The Baader Hyperion Aspheric 31mm eyepiece is a winning eyepiece for multiple reasons.
If you want more out of your view without adding weight or cost, it sounds like you need to check this eyepiece out.
It’s ready for attachment to 2” rigs, provides a very wide 72-degree AFOV, and provides as much pinpoint sharpness as you can get from an affordable eyepiece.
Here’s the truth about it from the good to not so good.
Baader Hyperion Aspheric 31mm Eyepiece Review
✔️ Best Feature: Aspheric lenses
❌ Worst Feature: Not for 1.25” assemblies
👌 Ideal For: Low-Medium Magnification, Super Wide FOV, Planets, DSO, Beginners, Intermediates
- Barrel Size: 2”
- Apparent Field of View: 72 degrees
- Focal Length: 31mm
- Eye Relief: 17mm
- Field Stop Diameter: 38mm
My Verdict: If you’re looking for a wide-angle upgrade and you’ve heard of Baader, you should opt for the Hyperion Aspheric eyepiece. In my opinion it’s priced appropriately, provides great correction of aberrations, and it’s easy and comfortable to use for all, including those who wear glasses.
Who is the Baader Hyperion 31mm Aspheric Best Suited to?
The Hyperion Aspheric 31mm eyepiece is a good eyepiece for beginner and intermediate telescope users. I think it’s priced just right to consider as an upgrade, and it performs almost as well as more expensive eyepieces.
Expert users, mainly nit-picky expert users, may find the Aspheric lens fun to use due to its lightweight and versatile platform, but to squeeze out that 10% of performance you’re looking for may require doubling the budget.
How Does the Baader Hyperion 31mm Aspheric Perform?
The Hyperion Aspheric 31mm eyepiece is a great performer. It’s not flawless like ones that cost more than twice its price, but it has excellent performance for its price point.
It provides almost zero chromatic aberration and almost zero field curvature. Keyword here? Almost.
However, this should not be a deterrent to buying the Baader eyepiece as it’s affordable, provides huge performance improvement than inferior ones, and is said to be better than Baader’s traditional Hyperion series.
The Aspheric eyepiece offers a lot, and its lightweight and versatile build makes it a winner for any 2” setup.
Features & Benefits
Aspheric Lenses
To bring lightweight and affordable benefits to the table, the Hyperion eyepiece is made with aspheric lenses. In a wide-angle eyepiece, it can help with spherical aberration correction in producing a flat field that extends to off-axis objects.
This eyepiece has 6 elements in 4 groups for superb multi-element performance.
If you look for it, you will see some slight coma at the very extreme edges of the FOV, but it’s virtually unnoticeable with the wide angle seeing. With scopes f/6 and slower, you won’t need a coma corrector.
While aspheric lenses usually consist of an unpolished molded plastic aspheric lens to keep the costs down, the more expensive eyepieces will incorporate glass aspheric lenses.
72-degree AFOV
The Baader eyepiece offers a super-wide 72-degree AFOV. This is plenty expansive enough to explore large objects at lower power without overwhelming the human eye. For example, seek out the Andromeda Galaxy, dense portions of the Milky Way, and open star clusters with this generous field of view.
It also has good eye relief of 17mm, so it should be able to accommodate buyers who wear glasses. You won’t need to press the balls of your eyes to the cups and roll them around. It’s comfortable to use and provides excellent seeing that puts you in the sky among the stars.
Lightweight
The Baader Hyperion Aspheric eyepiece is very lightweight weighing in at 17.4 oz for a 72-degree 31mm eyepiece.
It’s light and easy to handle thanks to its aspheric optical assembly that helps to cut down on glass without compromising optical quality.
This is the lightweight addition to your rig where you won’t have any balancing or focuser creeping issues.
Limitations
Not for 1.25” Assemblies
The Hyperion eyepiece has a 2” barrel but is really not designed to be used with 1.25” assemblies even though a free adapter is included. The eyepiece is limited in a way due to the focuser drawtube, 1.25” adapter, and the secondary mirror in a Newtonian in which it will cause vignetting or light loss up to 25% around the edges of the field of view. It should really only be used with 2” assemblies.
Popular Questions
Yes, projection photography can be done with the Baader Hyperion Aspheric eyepiece. It has M43 and SP 54 system lens threading. It can also be used with adapter threads to fit your specific camera to the eyepiece.
Yes! You can use these long focal length 2” eyepieces with interchangeable eyepiece astro binoculars as long as the IPD range is 56 mm and wider.
Baader Phantom Coating Group is the anti-reflective coating technology used to coat the lens elements in the Hyperion Aspheric 31mm eyepiece. The term “Group” indicates that each element has a customized coating formula specific to that element.
The results of this coating technology provide improved light transmission, zero glare, and anti-reflectivity benefits across the entire visible color spectrum.
The warranty is not as cut and dry for those outside of the EU states. While it can be assumed that it will be covered by a 1-year warranty, it’s best to insure your purchase with the vendor you are purchasing it from.
Conclusion
I believe the Hyperion Aspheric eyepiece may be the type of upgrade you need to improve your views for sharper, clearer, and high-contrast benefits.
It’s not the most expensive eyepiece, but that is exactly what makes it attractive to many. You don’t have to spend a fortune to get the performance you’re after.
