10x50 Binoculars

What does 10x50 mean?

The 10 is the magnification: a deer 500m away looks as if it were 50m away. The 50 is the diameter of each objective lens in millimetres, and lens area decides how much light the binoculars can collect. A 50mm lens has about 40% more area than a 42mm one, which is why a 10x50 looks brighter once the light starts to go, giving a clear, sharp view in low light when a smaller pair turns grey.

Divide 50 by 10 and you get the exit pupil, 5mm, the width of the beam of light that reaches your eye. In daylight your own pupil closes to 2mm or 3mm, so any decent binoculars look bright. At night it opens to somewhere between 5mm and 7mm (less as you get older), and that is where the bigger beam earns its keep. Two more figures turn up on spec sheets: twilight factor, the square root of magnification times lens size (22.4 for this size), and relative brightness, the exit pupil squared (25). The RSPB's guide to binocular terms explains the rest of the numbers on the box.

10x50 vs other sizes

The question most buyers ask is whether the extra 8mm of lens is worth the extra weight. In the same series it costs surprisingly little: the Hawke Endurance ED, GPO Passion HD and Bushnell Engage EDX in 10x50 each weigh about 100g to 115g more than the 42mm version.

Pick 10x50 if you are often out at first or last light or under the stars and don't mind the extra bulk. Pick 42mm binoculars for long days hiking, or 8x42 binoculars if you mostly watch small birds in trees, where a wider view helps you find them. Walkers who count every gram should look at the 8x32 binoculars instead. Going up to 12x adds reach, but every wobble is magnified too; 7x50 binoculars are the classic marine size because they are easier to hold steady on a moving deck.

Compare every pair on this page

All share the same 50mm lens and 5mm exit pupil, so the differences come down to glass quality, field of view, build and warranty. Specs are from each maker's listing; prices move daily, so check the cards above for today's figure.

The Endurance ED comes in black or green with identical optics. Every model has twist-up eyecups and a centre focus wheel, with a dioptre adjustment for the difference between your eyes (built into the focus wheel on the GPO), and comes with a carry case and strap.

What to look for in 10x50 binoculars

• Porro or roof prism. Classic porro prism binoculars, with the wide zig-zag shape, give a bright, three-dimensional view for little money: the Nikon Action, Pentax SP and Celestron UpClose G2 sell for well under £150, though they are bulkier and not always fully waterproof. Roof prism binoculars, like all four here, are slimmer and easier to seal against water, but need phase and mirror coatings to match a good porro prism design for contrast.
• ED glass. Extra low dispersion elements cut chromatic aberration, the purple and green colour fringing round a bright Moon or a gull against a white sky. The Endurance ED and Engage EDX have it, the Kowa does not, and the GPO relies on its HD glass and coatings.
• Field of view. A wider view makes it easier to find a star cluster or follow a bird. The Engage EDX leads at 113m; the Kowa is narrowest at 87m.
• Eye relief. Glasses wearers need around 15mm or more to see the whole view with the eyecups twisted down. The Kowa's 19.5mm is the most generous figure on this page.
• Build. From 740g (Kowa) to 960g (GPO). Magnesium bodies on the Engage EDX and Passion HD feel solid; polycarbonate keeps the Kowa and Endurance lighter and cheaper. A harness takes the load off your neck on a long day.
• Weather sealing. All four binoculars are waterproof and nitrogen filled, so they won't mist up inside when you come in from the cold. The Engage EDX carries an IPX7 rating, meaning it survives being dunked to 1m for 30 minutes.
• Tripod adapter. For stargazing or long outdoor sessions over water, a tripod transforms the view. Most full-size roof prism binoculars have a threaded socket under a cap at the front of the hinge; check the listing before you buy an adapter.

Best 10x50s at each budget

Under £300: the Kowa SV II is the lightest pair on the page and the easiest to use with glasses. Its 87m view is narrow and it only focuses down to 5.5m, so it suits stars, hills and estuaries better than garden birds. See the full range on our Kowa binoculars page.

£300 to £400: the Hawke Endurance ED brings ED glass and a no-fault lifetime warranty to mid-range money, and its close focus of about 2m to 2.5m makes it the best all-rounder here. The Bushnell Engage EDX has the widest view, 92% light transmission through its dielectric-coated prisms and an EXO Barrier coating that sheds rain, fog and fingerprints. Compare both full ranges on Hawke binoculars and Bushnell binoculars.

£1,000 plus: the GPO Passion HD has a magnesium and aluminium body, a micro bridge that balances it in the hand and a measured 91% light transmission. It is the heaviest at 960g. More from the German maker on our GPO binoculars page. Above this sit the Swarovski EL and Zeiss models, at well over £2,000.

10x50 binoculars for stargazing

Ten times fifty is often called the classic astronomy size: big enough to show thousands of points of light you can't see with the naked eye, small enough to hold without a mount. Many astronomers say good binoculars are the best first instrument to own before a telescope, because the wide view makes it easy to find your way round the sky, while a telescope only shows a tiny patch at a time. What you can expect to see:

• The Moon: craters, mountains and the dark seas, best along the line between light and shadow a few days either side of first quarter.
• Jupiter: a tiny bright disc with up to four Galilean moons strung out beside it, shifting position night to night.
• Saturn: an elongated dot. You need a telescope at 50x magnification or more to see the rings clearly.
• Star clusters: the Pleiades in autumn and winter, the Double Cluster in Perseus and the Beehive in Cancer all look superb.
• Nebulae and galaxies: the Orion Nebula shows as a misty glow, and the Andromeda Galaxy as a faint oval smudge under dark skies.
• The Milky Way: from a properly dark site, sweeping along it on a summer night is the best show binoculars can give.

Light pollution only matters for the faint objects; the Moon and planets are bright enough to see from town. For the rest, find a dark site near you on the Dark Sky Discovery map, many of them in UK national parks. Rest your elbows on a wall, lie back on a reclining garden chair or use a tripod, and never point binoculars at the Sun. If you want more reach or more light, the 12x56 and giant 25x100 pairs on our astronomy binoculars page go deeper, though they need a tripod, while a 10x binocular pair is the one you can carry out on a whim.

Wildlife, hunting, boats and sports

• Deer and stalking: in England and Wales deer may only be shot from one hour before sunrise to one hour after sunset, and those first and last hours are exactly when 50mm lenses show more than a 42mm pair. See our hunting binoculars for 8x56 and 10x56 options too.
• Birdwatching and wildlife: great on estuaries, reservoirs and sea watches in winter light. In thick woodland lighter 8x binoculars are easier; browse every size in birdwatching binoculars.
• Boats: a 10x is hard to hold steady on a rolling deck, so most sailors choose a 7x50.
• Sports, safari and travel: plenty of reach for a racecourse or game drive, but bulky in a bag. For a pocket, choose compact binoculars, which fold small enough for a jacket.

How to hold 10x50s steady

Ten times magnification also magnifies every tremor, and a 10x50 is heavy enough to tire your arms on a long session. Tuck your elbows into your chest, rest your thumbs on your cheekbones and breathe out slowly before you look. Lean on a tree, a gate or a car roof when you can. For the night sky or a long watch over water, a tripod adapter or monopod makes the biggest difference of all. The Which? binoculars buying guide has more tips on choosing and using them.

Frequently asked questions

Are 10x50 binoculars good for beginners?

Yes. They are a forgiving, all-round size that works by day and by night, so they are a common first choice. If you will carry them all day on a hike, a smaller 42mm pair is lighter.

Are 10x50s too heavy to hold?

Not for most people. The binoculars here weigh 740g to 960g, about 100g more than a 42mm pair. A comfortable neck strap or harness helps, and a tripod is worth having for stargazing.

Can you see planets through a 10x50?

You can see them, but only as bright dots or tiny discs. Jupiter's four largest moons show clearly, Saturn looks oval, and you need a telescope for rings or cloud bands.

Are 10x50s any good for bird watching?

For open country, yes: estuaries, the coast and moorland, especially in poor light. For small birds in hedges and trees, an 8x32 gives a wider, steadier view.

Do they suit glasses wearers?

All four here do. Twist the eyecups fully down so your glasses sit close to the eyepiece; the Kowa gives 19.5mm of eye relief, the Hawke and GPO 17mm and the Bushnell 15mm.

Should I buy 10x50 or 12x50?

For most people 10x50. A 12x50 shows a little more detail but has a smaller exit pupil and a narrower view, and it is harder to hold steady without a rest.