Baader Planetarium

Baader Hyperion 13mm

A 13mm Baader Hyperion: the workhorse magnification where most galaxies, globulars and nebulae look their best, from a modular 68-degree workhorse you can rebuild into other focal lengths.

82/ 100

Polaris Score

Optical quality · Immersion · Comfort · Value

See the breakdown ↓

What it's for

Low power · wide fieldHigh power · narrow field

Medium power. At 13mm this is the workhorse magnification where most galaxies, globulars and nebulae look their best.

Apparent Field

68°

Barrel Size

1.25"

Eye Relief

20mm

Focal Length

13mm

From$217

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The spacewalk

You don’t look at a field.
You look into the sky.

Every number on the spec sheet matters less than one feeling: how much sky wraps around your eye. Widen the apparent field and watch the black edge of the eyepiece slip away.

68° apparent field

At 68°, the black rim sits out at the corner of your attention rather than in front of you.

See this field in your own scope in the Simulator →

01What it's good at

What it's best at — and the trade-offs.

Best at

✓Modular build: fine-tuning rings and a screw-off bottom let you shift the focal length.

✓A relaxed 20mm of eye relief that makes long observing sessions genuinely comfortable.

✓At 13mm it lands squarely in medium power territory, exactly where most deep-sky objects look their best.

Trade-offs

!The outer field softens in fast scopes below about f/6; it is happiest at f/6 and slower.

!Some field curvature means a slight refocus between center and edge on extended objects.

!Heavier and longer than a simple wide-field of the same focal length.

02In your telescope

One eyepiece. A different job in every scope.

An eyepiece has no magnification of its own — the telescope decides. The same eyepiece becomes 37× and 1.8° of sky in a little refractor, or 156× and a tight frame in a long SCT. Here’s what it does across common scopes.

Small apo refractor

480 mm · f/5.5

Magnification

37×

True field

1.8°

Exit pupil

2.4 mm

37× across a 1.8° field at a 2.4mm exit pupil, right in the deep-sky sweet spot, bright and easy on the eye.

8-inch Dobsonian

1200 mm · f/6

Magnification

92×

True field

44′

Exit pupil

2.2 mm

92× across a 44′ field at a 2.2mm exit pupil, right in the deep-sky sweet spot, bright and easy on the eye.

12-inch Dobsonian

1500 mm · f/5

Magnification

115×

True field

35′

Exit pupil

2.6 mm

115× across a 35′ field at a 2.6mm exit pupil, right in the deep-sky sweet spot, bright and easy on the eye.

8-inch SCT

2032 mm · f/10

Magnification

156×

True field

26′

Exit pupil

1.3 mm

156× across a 26′ field at a 1.3mm exit pupil, crisp medium power for galaxies, clusters and planetary nebulae.

Exit pupil is how wide the beam of light leaving the eyepiece is. Around 5–6 mm is bright and immersive under dark skies; push much past 6 mm and you waste light, and under light pollution a smaller exit pupil shows more contrast.

02In plain English

The numbers, in plain English.

Focal lengthMid power

13mm

Around 92x in an 8 inch f/5.9 Dobsonian and 156x in an 8 inch SCT. This is the magnification that suits globular clusters, brighter galaxies and larger planetary nebulae, and it is where many observers spend most of a session.

Apparent fieldWide

68°

At a mid focal length the 68 degree apparent field gives a genuinely useful true field: enough to hold a large cluster whole while still working at a power that darkens the sky background.

Eye reliefExcellent

20mm

Comfortable with or without glasses, and relaxed enough that you are not fighting to hold your eye position while studying faint detail.

BarrelStandard

1.25"

Fits any telescope's focuser or diagonal without adapters, which keeps this a straightforward addition to an existing eyepiece case.

OpticsModular

Baader multi-coatings

Full coatings maintain contrast across many elements, and the modular design allows focal length changes with accessory rings. In fast telescopes some edge softening appears, which is normal for this class.

03What comes alive

The targets this eyepiece was born for.

Comes alive

M13 globular cluster

Resolves to the core with pinpoint stars across the field.

Excellent

The Whirlpool (M51)

Two cores and a hint of the bridging spiral arm.

Comes alive

The Dumbbell Nebula (M27)

The apple-core shape framed with dark sky around it.

Excellent

M81 and M82

Both galaxies in one field, one soft, one edge-on and streaky.

Excellent

The Ring Nebula (M57)

A clean smoke ring at a comfortable scale.

Excellent

The Trapezium in Orion

Four stars split cleanly inside the glowing nebula.

04Role in a collection

Where it sits in your eyepiece case.

A good eyepiece collection isn’t a pile of glass — it’s two or three focal lengths that hand off from wide to tight. This is the anchor at the bottom of the ladder: the one you find and frame with. You buy it once, and it stays your low-power eyepiece for life.

32 mm

Low power · wide field

Find, frame and sweep. Your widest true field and the lowest useful magnification, the eyepiece you reach for first.

Veil Nebula · Pleiades · Milky Way star clouds

13 mmThis one

Medium power · the workhorse

Where most deep-sky objects look their best, galaxies, globulars and planetary nebulae at a comfortable scale.

M13 · Ring Nebula · most galaxies

7 mm

High power · detail

Planets, the Moon at the terminator, tight double stars and the smallest planetary nebulae. Steady-air nights only.

Jupiter · Saturn · lunar craters

04Build around it

What it pairs with.

The telescope

What it goes into

Any 1.25-inch focuser

Fits essentially every telescope made.

Fast, short scopes love this field

A fast Newtonian or refractor turns this focal length into a rich, wide sweep.

Pair it

What extends its range

A high-power eyepiece (~8mm)

Locate and frame with this one, then swap to high power for planets and small objects.

Filter it

What transforms the view

A mild broadband light-pollution filter

Lifts contrast on galaxies and clusters from the suburbs at medium power.

02The Polaris Score

How it scores, and why.

82/ 100

Baader Hyperion 13mm

Judged as the workhorse magnification where most galaxies, globulars and nebulae look their best, it earns its score on a relaxed 20mm of eye relief that makes long observing sessions genuinely comfortable. The comfortable eye relief lifts it further. It is honest about being a specialist, not an all-rounder.

Optical quality

Immersion

Comfort

Value

Polaris weighs how well the eyepiece does the job it was designed for — optics, immersion, comfort and value — never list price or brand.

03Who it's for

An honest fit check.

Buy it if you

✓Observers who want the workhorse magnification where most galaxies, globulars and nebulae look their best.

✓Anyone who observes in eyeglasses; the eye relief here is long enough to see the whole field.

✓Observers who want a comfortably wide field without paying ultra-wide prices.

Look elsewhere if you

!Anyone chasing the absolute widest field, who should look at a 100-degree eyepiece.

!Grab-and-go observers watching every gram, since this is not the lightest option.

!Planetary specialists who want the last ounce of high-power contrast from an orthoscopic.

05The numbers

Full specifications.

Optical

Focal Length13mm

Apparent Field68°

Comfort & handling

Eye Relief20mm

Fit & build

Barrel Size1.25"

Editor’s Take

Sweep it across a rich star field and the reason to own this focal length is obvious in a second. That is what the Hyperion is for.

— The Skynocular verdict

06Alternatives

For a different goal, start here.

Wider, lower power

Baader Hyperion 21mm

The same optics with more true field, for framing larger objects and finding your way around.

→More magnification

Baader Hyperion 8mm

The same line at higher power, for planets and the smallest deep-sky detail.

→Cross-shop

Explore Scientific 68°

A natural alternative at a nearby price point, if you want to compare field and feel before committing.

→

Baader Hyperion 13mm

You don’t look at a field.You look into the sky.

What it's best at — and the trade-offs.

One eyepiece. A different job in every scope.

The numbers, in plain English.

The targets this eyepiece was born for.

Where it sits in your eyepiece case.

What it pairs with.

How it scores, and why.

An honest fit check.

Full specifications.

For a different goal, start here.

You don’t look at a field.
You look into the sky.