This depends on two factors:

• How you intend to use them
• Your budget

You need very different binoculars for hunting and birdwatching, for example.

You can pay a thousand GBP, EUR or USD, or more, for a really good pair; or go for cheap binoculars, but you can get a serviceable pair for a tenth of that, or if you’re lucky much less.

Binoculars have two measurements; you’ll see them expressed as “7x35” or “10x40”.

The first number is the magnification. You might think higher is always better, but if you are hand-holding them, they will magnify every shake you make. For hand holding, 7x or 8x is best. For astronomy, say, you might want 10x or 20x, on a tripod. Avoid “zoom” binoculars, with adjustable magnification, that gimmick is traded against quality.

The second number is the diameter, in millimetres, of the “big” end. The bigger the number, the more light they let in, and so the brighter the image - but the heavier they are, and that’s significant if you have shakes, or will be using them all day. Big lenses also mean narrower field of view. For birdwatching 30-42 is usual.

A third factor is whether or not they are “gas sealed” (or “nitrogen filled”). Better pairs are, and will not let in water. You can even wash them. After using a pair that are not, in the rain, they can mist up internally, and that can leave a permanent residue on the inside of the lenses. Obviously, your need for this depends on where you live!

Try out binoculars for hunting, preferably on a dull day, and look at something in the shadows. Even mediocre sets work well on brightly-lit subjects, but they struggle in low light.

Look at edges with high contrast, like the ridge of a roof with the sun on the other side (but never look at the sun!) . Is it sharp, or is there a coloured haze along it? Repeat, but using the edge, not the middle of the field of view. Also, is the image generally sharp cross the whole field, or just the centre?

What’s the close focus like? Some pairs cannot focus nearer than 8 or 10 metres - no good for looking at butterflies or dragonflies. Good ones can focus down to 2 or 3 metres.

Always compare two or three types before buying. A good dealer will understand and help you to do this. Buying second-hand can save you money, or get more for the budget you have. And read online reviews.

Mine are 8x42 Leica Ultravid, used for birding, and I’m very happy with them