Baader Hyperion Mark IV Zoom Review: One Eyepiece?
The Hyperion Mark IV is the zoom that experienced observers actually keep, because its clickstops are firm, its coatings are excellent and it fits both 1.25 and 2 inch focusers. Buy it if you observe in cold or damp conditions where swapping eyepieces invites dew and dropped glass, or if you do outreach where handing one eyepiece to strangers is the practical choice. Skip it if you observe from a fixed chair in dry weather and want the widest possible field, because fixed eyepieces still beat any zoom at the low power end.
Five focal lengths in one barrel, a 68 degree field at the short end, and the compromise you accept at the long end.
Baader Planetarium Hyperion Universal Mark IV 8-24mm Zoom Eyepiece
~$396
A fourth generation 68 degree widefield zoom with defined clickstops at 8, 12, 16, 20 and 24mm, supplied with both 2 inch and 1.25 inch barrels.
Check price on AmazonSpecifications
| Focal lengths | 8, 12, 16, 20 and 24mm at defined clickstops |
|---|---|
| Apparent field | 68 degrees widefield |
| Barrels | Both 2 inch and 1.25 inch included |
| Other fittings | Some spotting scopes with a 1 3/8 inch thread |
| Coatings | Baader Phantom Coating Group multicoatings |
| Eyecups | Large adjustable rubber, small straight and winged foldable |
| Photography | M43 video and photo thread for afocal and projection work |
Specifications above come from Baader Planetarium's published specifications. Treat pricing as approximate, since Amazon pricing moves.
What it does well
- Clickstops that hold, so you know exactly what focal length you are at and can repeat it, which the smooth zooms cannot offer.
- Sixty eight degrees is a genuinely wide apparent field for a zoom, and it is the figure that makes this one worth its price.
- Both barrel sizes are included, so it works in a 2 inch focuser on a Dobsonian and a 1.25 inch diagonal on a refractor without an adapter.
- One eyepiece in and out of the focuser means fewer chances for dew, dust and dropped glass on a cold night.
Where it falls short
- The apparent field narrows as you zoom out to the longest focal length, which is exactly where you most want a wide field. This is inherent to zoom eyepiece design.
- It is heavy and can unbalance a light altazimuth mount or a small Dobsonian, which is a real nuisance rather than a theoretical one.
- At four hundred dollars it costs as much as several good fixed eyepieces, so the value case rests on convenience rather than optics.
- Eye relief varies through the zoom range, which spectacle wearers notice more than other observers.
What owners report
Published owner reports are unusually positive for a zoom, and the reason given is consistent: observers who had written zooms off after using cheaper ones describe this as the first that did not feel like a compromise at high power. Sharpness at the 8mm end draws specific praise, which matters because that is the planetary end.
The two criticisms that recur are weight and the narrowing field at 24mm. Owners of small Dobsonians and light altazimuth mounts mention rebalancing. Deep sky observers mention reaching for a wide fixed eyepiece for large objects. Neither group suggests the eyepiece is poor, only that it is not a complete replacement for a set.
Who it suits
- Observers who do outreach or public sessions, where one eyepiece is far easier to manage.
- Anyone observing in cold or damp conditions where opening the focuser repeatedly is a problem.
- Travellers, since one eyepiece replaces a case of them.
Who should skip it
- Deep sky observers whose priority is the widest possible low power field.
- Owners of very light mounts that a heavy eyepiece will unbalance.
- Anyone on a budget, where two or three good fixed eyepieces will show more for less.
Alternatives worth considering
Celestron 8-24mm Zoom Telescope Eyepiece with fully multi-coated optics
~$95
The same focal length range for a quarter of the price, with a noticeably narrower field and less refined correction. It is the sensible way to find out whether you like observing with a zoom before spending four hundred dollars.
Check price on AmazonSVBONY SV154 Telescope Eyepiece 2 inch, 70 degree super wide angle
~$53
A fixed 2 inch wide angle eyepiece for low power sweeping, which is precisely the job a zoom does worst. Pairing one of these with a zoom covers the range better than either alone.
Check price on AmazonKeep reading
- Zoom eyepiece vs fixed eyepieces
- Barlow vs a shorter eyepiece
- Eyepiece calculator
- Magnification calculator
- Sky-Watcher Classic 200 review
- Maximum useful magnification by aperture
This review draws on published specifications, manufacturer figures and the consensus of verified owner reviews. We have not tested this product ourselves, and we say so rather than implying otherwise. As an Amazon Associate we earn from qualifying purchases.
Frequently asked questions
Is a zoom eyepiece as good as fixed eyepieces?
At the high power end, a good zoom like this one is close enough that most observers cannot tell. At the low power end, fixed eyepieces win clearly, because a zoom's apparent field narrows as focal length increases. Our zoom eyepiece versus fixed eyepieces comparison goes through the tradeoff in detail.
What magnifications does it give on my telescope?
Divide your telescope's focal length by each clickstop. On a 1200mm Dobsonian, 24mm gives 50x and 8mm gives 150x. Our eyepiece calculator does this for your specific telescope and also reports the exit pupil, which is what tells you whether a magnification is usable.
Does it work with a Barlow?
Yes, and that is a common way to extend the range downwards for planetary work, effectively giving you a 4 to 12mm zoom with a 2x Barlow. Our Barlow versus a short eyepiece comparison covers whether that is the right way to reach high power.
Will it unbalance my telescope?
It might, on a small Dobsonian or a light altazimuth mount. It is a substantial eyepiece, and a tabletop Dobsonian in particular can tip forward. Tension control handles or a counterweight solve it, but check before assuming.
Is it worth four times the price of a cheap zoom?
If you use a zoom as your main eyepiece, yes, because the wider field and better correction at high power are exactly what you notice every session. If a zoom would be an occasional convenience, the cheaper Celestron does the job and leaves money for fixed eyepieces.
How we choose: we compare published manufacturer specifications, optical figures we can verify, and reviews from owners who have used the equipment under real skies. We do not test gear in person. Never point any telescope, finder or binocular at the Sun without a certified full-aperture solar filter fitted over the front of the instrument.
Recording your own eyepieces, exit pupils and sessions? The Observing & Astrophotography Planner is the paid version of these pages: 8 printable worksheets you fill in with your own numbers, plus the full PDF, $29.