Choosing the best binoculars
Where possible, it’s always best to try out binoculars before you buy them, as this is the best way to ensure you get the right combination of comfort, size, weight, ease of use and performance.
Six questions to consider when choosing binoculars
1. Will you be looking at a single object or several objects?
Do you want to look at one thing, such as a bird in flight, or watch several things simultaneously, such as race horses at a race track? In the first case, the binoculars’ magnification is more important than the field of view, and vice versa for the latter.
2. Will you be using the binoculars in low light?
If you plan to use your binoculars at sunrise or sunset, then the objective lens diameter, exit pupil and light transmission are all important.
- The objective lens diameter is the measurement of the lenses at the end of the binoculars. A larger objective lens diameter lets in more light, making the image appear brighter (all other factors being equal).
- The binoculars’ exit pupil tells you how much light is sent to your eye through the binoculars, and is calculated by dividing the size of the objective lens by the magnification.
- The binoculars’ light-transmission measurement will tell you what percentage of light reaches the eye after entering the binoculars. The lens coatings used in the binoculars can help reduce the amount of reflected light and increase the amount that reaches the eye. This helps improve the brightness and clarity of the image.
Compared with standard-sized binoculars, compact binoculars have a smaller objective lens diameter and exit-pupil measurement, so tend to work best in brighter daylight conditions.
These factors may be particularly important if you plan to use your binoculars for birdwatching at dawn or dusk, and should be considered in combination.
3. Do you need waterproof binoculars?
If you plan to use your binoculars outside, then you may want to consider a waterproof pair. This will keep the inner mechanics protected from an unexpected downpour and prevent any water getting in.
4. Will you be using your binoculars on the move?
If you plan to use your binoculars while out and about, it’s important to consider their size and weight. If you need to carry them for for long distances, a lighter, compact pair might be preferable. Compact binoculars can also have the added benefit of fitting into a coat or jacket pocket. Don’t forget to check the weight of the binoculars’ carrying case, too, as this will affect the overall weight.
While on the move, neck straps are a handy accessory for quickly and securely picking up and putting down your binoculars in between uses. Some armoured models can provide additional protection, and rugged armour can also make them easier to grip.
5. Do you wear glasses?
The binoculars’ eye relief tells you the furthest distance your eye can be from the eyepiece and still see the whole field of view. If you wear glasses, look for eye relief of more than 14mm, or 17mm for thick glasses.
Most binoculars have sliding eyecups or rubber eyepieces that can be rolled back, allowing the eye to sit closer to the lens. It’s best to try a number of pairs while wearing your glasses before buying.
6. Will you need a tripod?
Binoculars with a high magnification, anything from 10x upwards, can be harder to hold steady without the use of a tripod. Many standard-sized binoculars have a tripod mount built in, or will be labelled 'tripod adaptable'. If you will need to use a tripod, always check your binoculars are adaptable or already include a mount.
If you are considering a pair of high-magnification binoculars, it’s best to try them out before you buy. This way you can see if your hands are steady enough to use them without needing a tripod.