Explore Scientific 16mm 68° — image 1
Explore Scientific

Explore Scientific 16mm 68°

A 16mm Explore Scientific 68° Series: the workhorse magnification where most galaxies, globulars and nebulae look their best, from a waterproof 68-degree wide-field that hits the sweet spot of field, comfort and price.

81/ 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 16mm this is the workhorse magnification where most galaxies, globulars and nebulae look their best.

Apparent Field
68°
Barrel Size
1.25"
Eye Relief
16mm
Focal Length
16mm
From$109.99

Lowest in 90 days

Price tracked by PolarisObserved 54 timesTracking since Aug 2026

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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.
Try this eyepiece on your own scope in the Simulator →
01What it's good at

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

Argon-purged and waterproof against dew and cold.
Best at
✓Argon-purged and waterproof against dew and cold.
✓A 68-degree field that frames deep-sky objects with room to spare.
✓At 16mm it lands squarely in medium power territory, exactly where most deep-sky objects look their best.
Trade-offs
!The outer field softens in very fast scopes below about f/5.
!The 2-inch long focal lengths are heavy.
!Not as immersive as an 82-degree or 100-degree eyepiece.
02In your telescope

One eyepiece. A different job in every scope.

30× in a small refractor, 127× in a long SCT

An eyepiece has no magnification of its own — the telescope decides. The same eyepiece becomes 30× and 2.3° of sky in a little refractor, or 127× 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
30×
True field
2.3°
Exit pupil
2.9 mm
30× across a 2.3° field at a 2.9mm exit pupil, right in the deep-sky sweet spot, bright and easy on the eye.
8-inch Dobsonian
1200 mm · f/6
Magnification
75×
True field
54′
Exit pupil
2.7 mm
75× across a 54′ field at a 2.7mm exit pupil, right in the deep-sky sweet spot, bright and easy on the eye.
12-inch Dobsonian
1500 mm · f/5
Magnification
94×
True field
43′
Exit pupil
3.2 mm
94× across a 43′ field at a 3.2mm exit pupil, right in the deep-sky sweet spot, bright and easy on the eye.
8-inch SCT
2032 mm · f/10
Magnification
127×
True field
32′
Exit pupil
1.6 mm
127× across a 32′ field at a 1.6mm 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.
03In plain English

The numbers, in plain English.

16mm FL · 68° AFOV · 1.25"
Focal lengthMid power
16mm
About 75x in an 8 inch f/5.9 Dobsonian and 127x in an 8 inch SCT. The general-purpose range where most deep-sky observing happens: dark background, resolved cluster stars, visible galaxy shape.
Apparent fieldWide
68°
Sixty-eight degrees gives an open, comfortable view without demanding the correction that extreme fields require from a fast telescope. It is the most practical field width for everyday observing.
Eye reliefComfortable
16mm
Enough for relaxed viewing and usable with thin glasses, which makes this range easier to live with than the wider 82 and 100 degree models.
BarrelStandard
1.25"
Fits any focuser or diagonal without adapters, and the modest weight keeps a Dobsonian in balance when you swap it in.
OpticsAll-rounder
EMD fully multi-coated
Enhanced coatings and a sealed argon-purged body at a mid price. The 68 degree line is the one most people end up using most, because nothing about it fights the telescope or the observer.
04What comes alive

The targets this eyepiece was born for.

M13 globular cluster, The Whirlpool (M51), The Dumbbell Nebula (M27), M81 and M82, The Ring…
M13 globular clusterComes alive
M13 globular cluster
Resolves to the core with pinpoint stars across the field.
The Whirlpool (M51)Excellent
The Whirlpool (M51)
Two cores and a hint of the bridging spiral arm.
The Dumbbell Nebula (M27)Comes alive
The Dumbbell Nebula (M27)
The apple-core shape framed with dark sky around it.
M81 and M82Excellent
M81 and M82
Both galaxies in one field, one soft, one edge-on and streaky.
The Ring Nebula (M57)Excellent
The Ring Nebula (M57)
A clean smoke ring at a comfortable scale.
The Trapezium in OrionExcellent
The Trapezium in Orion
Four stars split cleanly inside the glowing nebula.
05Role in a collection

Where it sits in your eyepiece case.

Where it sits across 3 focal lengths

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
16 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
06Build around it

What it pairs with.

The telescope · Pair it · Filter it
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 (~10mm)
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.
07The Polaris Score

How it scores, and why.

81/100
81/ 100
Explore Scientific 16mm 68°

Judged as the workhorse magnification where most galaxies, globulars and nebulae look their best, it earns its score on a 68-degree field that frames deep-sky objects with room to spare. The comfortable eye relief lifts it further. It is honest about being a specialist, not an all-rounder.

Optical quality
80
Immersion
79
Comfort
84
Value
84

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

08Who it's for

An honest fit check.

Observers who want the workhorse magnification where most galaxies, globulars and nebulae…
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.
09The numbers

Full specifications.

4 measured and stated values
Optical
Focal Length16mm
Apparent Field68°
Comfort & handling
Eye Relief16mm
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 68° Series is for.

— The Skynocular verdict
10Alternatives

For a different goal, start here.

2 alternatives, each mapped to the goal it wins at
Wider, lower power

Explore Scientific 68° Series 28mm

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

→
Cross-shop

Baader Hyperion

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

→