Aurosports 20x70 Binoculars

Is the Aurosports 20x70 Binoculars worth buying?

Yes, the Aurosports 20x70 Binoculars are worth £43.99 if you want a 70 mm objective and you watch from a seated or propped position in daylight. They give you the biggest front lens in this price band, 525 owners rate them 4.4, and the 3.5 mm exit pupil keeps the view bright until the light starts to go.

They are the wrong choice if you walk all day: 1.21 kg on a neck strap tires you quickly, and 20x magnifies every shake in your hands until the image is useless. For a window watcher, a stargazer or a hide with a tripod, the 70 mm of glass and the 26 mm eye relief do exactly what you paid for.

What does the 3.5 mm exit pupil mean in real use?

Divide the 70 mm objective by the 20x magnification and you get a 3.5 mm exit pupil, the beam of light that reaches your eye. That is wider than your pupil opens in daylight, so the view stays comfortable, and the 70 mm lens collects almost three times the light of a 42 mm pair, which pays off in the last hour before dusk.

The relative brightness figure of 3.5 tells the same story as a single number, and 26 mm of eye relief means glasses wearers can keep the full field. The 3.4 degree field of view is narrow, so a bird at 100 m sits in a small window, and the +/-5 diopters let you set each eye separately.

What comes in the box and how do you live with 1.21 kg?

The box holds the binoculars, a carrying bag, a cleaning cloth and a neck strap, and nothing else. A tripod and a smartphone adapter both fit the body, but neither is included, so add them to the £43.99 if you want steady viewing or photographs through the eyepiece.

At 1.21 kg these are full-size binoculars, and the rubber-coated body has an O-ring seal at the lens to keep dust out. The neck strap will carry them, but an hour-long walk is a chore; a tripod or a window ledge is the realistic way to use 20x for any length of time.

Where do the Aurosports 20x70 Binoculars fall short?

Rain is the weak point: they have no water resistance at all, so a shower ends the session and you should keep them in the bag when the sky darkens. The 1.21 kg weight also rules out a long hike, and 20x makes hand-held viewing pointless because the image shakes too much to read detail.

The 3.4 degree field of view is narrow, so finding a moving bird takes practice, and the manual focus wheel is slower than the centre-focus knobs on lighter pairs. A tripod and a phone adapter each cost extra on top of the £43.99, which changes the value if you need both.

How do they compare with the Kylietech 12x42 and the Celestron Outland X?

The Kylietech 12x42 at £25.99 gives the same 3.5 mm exit pupil in a 42 mm tube, and it is waterproof and fogproof, so it survives the rain the Aurosports cannot. It weighs far less and costs £18 less; choose it if you walk and watch birds in British weather.

The Celestron Outland X 8x42 at £85 gives a 5.25 mm exit pupil, the widest on this page, with nitrogen purging and a limited lifetime warranty. That is £41 more than the Aurosports, but it stays bright at dusk and survives a downpour; choose it if you want one pair for all seasons, and choose the Aurosports if you want the most glass for the money and you watch from a fixed spot.