10-30x42 zoom monocular

One hand, one pocket

A monocular is half a pair of binoculars. This one weighs 279 g according to the supplier and measures 53 x 174 mm, so it fits a jacket pocket and comes out with one hand. It suits walkers who want a quick look at a waymark across a field, travellers, and anyone who watches sport or wildlife now and then rather than for hours at a time.

How to use the zoom

Start at 10x. That is where the view is widest, brightest and steadiest, with an exit pupil of 4.2 mm. Find what you want to look at, focus with the ridged ring, then turn the zoom ring towards 30x for more detail. At 30x the exit pupil is only 1.4 mm and every movement of your hand is enlarged three times as much, so the top of the zoom range works best in bright light with the monocular braced against a post, a wall or a car roof.

Zoom optics are a compromise. A fixed magnification monocular or a good pair of binoculars usually gives a cleaner view at the same power. What a zoom gives you is flexibility in a very small package.

Glass and build

The supplier lists a BaK-4 prism, fully multi-coated optics with a green coating, a 16 mm eyepiece lens and a twist-up eyecup. The body is metal with a rubber covering. For long sessions of birdwatching, binoculars are more comfortable, because both eyes work together: see our binoculars.