Don’t worry about being too specific. Any binocular will magnify your view, though different features will make some more appropriate than others. Browse the criteria below, and you will be better informed to make that choice. One over-riding tip – never look at the sun through binoculars, and that means being very careful when following aircraft or birds in flight!

Denomination
Aside from instrument quality, two figures are used to denominate a binocular - 8x 21, or 10x 50 for example.

• The first states the magnification (power) on a standardised scale. Think of this as giving an image eight times or ten times closer to your subject.
• The second figure is the diameter of the front (objective) lens, which indicates both how much light can enter that instrument, and what sort of size the binocular will be.

Power
The more you magnify your subject, the less of it you will see. If at eight times you can see an entire aircraft, at twelve times you will probably only see the tailplane. This effect is often described as the field (or width) of view, so the greater the power, the narrower the field of view.

Reducing the field of view with more power has several effects. Your hand movement becomes greater in proportion to your picture (shake becomes more apparent); targeting becomes harder as you look through a narrower vision cone; you have less light to work with.

Most of our binoculars will be 6x up to 12x magnification

• At 6-8x you will have a wide field of view, hardly notice any shake, and find the binoculars easy to use.
• At 10x you will have a bigger subject, more distance potential, and a little more shake.
• At 12x you will have a still larger subject, a lot more shake (especially with the fingertip grip of a pocket compact), much less width of field, and less definition.
• Above 12x you will need some means to steady the binocular, or to fit it to a tripod.

Size
Simple physics at work here. The larger the front (objective) lenses, the greater the light gathered. The more light, the sharper (more detailed) your picture. Think of your pupils being as wide open as the front lenses – that’s how much light you are receiving! Your pupils open wider in darker conditions not to give you a bigger picture, just to pick up more light (and therefore detail). So a bigger binocular will give a more detailed picture.

A smaller binocular is easier to carry, and therefore more likely to be with you when needed.  Thus your choice will be on the compromise between size and image quality.

Format
Apart from size, there are two standard formats, ZCF (porro prism) designs, and DCF (roof prism) designs. The ZCF format offsets the image since the prisms are side by side. Where the offset increases the distance between objective lenses over the eyepiece (diopter) lenses, you can expect more of a 3D effect than with other formats. This is certainly true of the traditional full-size ZCF binocular.

You may find one design more comfortable than the other, but the image quality does not depend on the type.

Binoculars versus Telescopes
(land telescopes are often called "Spotting `scopes")
Binoculars are usually hand-held instruments, give a 3D image over the near distance, and can be used quickly, virtually anywhere.

Depending on the conditions, at some point over 12x magnification standard binoculars cease to be effective. If you need more power to magnify a small object such as a bird’s nest, or for a coastal view, you will need to consider a telescope, or possibly a large observation point binocular.

Most telescopes have a zoom facility ranging from about 18 or 20x up to 60x or more. They are easily set-up, and most of our models are waterproof. Observation binoculars often have fixed power but very large objective lenses, they are less versatile but can be more comfortable for sustained viewing and give the 3D effect (which telescopes do not) over extended distances. Both need to be tripod mounted, both can be used for star-gazing, and, being prismatic, will always give a corrected image, not the inverted image of an astroscope.

Low Light
For poor light (heavy woodland, dusk, star-gazing, etc.), you need a binocular with large objective lenses, and large exit pupil (the picture presented to your eye). 7x 50, 8x 56, or 9x 63 are the most suitable.

Quality
There is no guide to quality in the denomination figures. Generally the more expensive the binocular, the better it will achieve the light transfer to your eyes, usually resulting in less eye strain, deeper focus, and a sharper picture. Techniques to achieve this vary, with some or all coming into play at various price points. Build quality will also improve with price. Be aware though, that numbers produced will drop rapidly as the quality specification increases, so the price steps will increase for ever smaller improvements.

Your eyes are very sensitive, so if you are likely to use your binoculars intensively, or for long periods, or for a lot of movement, you would be well-advised to buy medium to good quality instruments. Look out for BAK4 prisms and multi-coating.

Coatings
Anti U/V coatings are quite common on the objective lenses, these have an anti-glare effect, and help sharpness, though the less expensive ruby (or strong ruby as applied to Marine models) anti U/V coatings, can affect colour slightly.

All of our binoculars have coated lenses and prisms to improve light transmission. Those with full multi-coating offer the best transmission (dependent on the glass used), having multiple coatings on each glass surface.

Tripod Mounting
Almost all of our full sized binoculars incorporate a tripod mounting point, but you will require a tripod bracket.

In brief:
If you are back-garden bird-watching, out walking, canal boating, going to concerts/matches, or National Trust visits, you can’t go far wrong with an 8x pair. For viewing wildlife, horse racing, athletics, etc., perhaps a 10x, and for building inspection, aircraft, coast watching etc., possibly a 12x would suit you - if you have a steady grip. For higher magnification use a telescope on a tripod.

In good daylight pocket compacts are fine, though you will always have a better picture with a larger binocular. Take care of your eyes, look out for BAK 4 prisms and eye relief if you use binoculars more than briefly. If possible keep down in power, go for definition instead, and remember - NEVER look at the sun!