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Glossary Coating: A microscopic chemical is applied to the lenses in order to improve light transmission and minimise reflection. The best coating is full multi-coating.

Choosing the right binoculars can be a difficult and confusing task. To help you make the right decision we have made this small guide and glossary.

Magnification: 10x magnification means that an object appears 10 times larger when seen through the binoculars. Objective lens diameter: The diameter in millimetres of the objective lens.

What does 7x42 mean?

Choosing a pair of binoculars


For all binoculars, two numbers separated by an x are specified. They define the magnification of the binoculars and the objective lens diameter in millimetres, respectively. A magnification of less than 7 times gives the binoculars a wide field of view and good depth of field, but not as much detail. A magnification of 7 or more gives a more detailed picture, but at the cost of a narrower field of view and less depth of field. Good all-round binoculars have a magnification of between 7 and 10 times. The objective lens diameter determines the amount of light that enters the binoculars. In daylight, an objective lens diameter of up to 42mm is sufficient. A large diameter (+42mm) allows a lot of light in and is a good choice for poor light conditions.

For hunting, an objective lens diameter of at least 35mm is recommended. If you need superior performance at dusk or in dark conditions, the objective lens diameter needs to be larger.

Many riflescopes are available with variable magnifications, enabling you to find the magnification best suited to the terrain, distance and light conditions in question. As described above, it comes down to weighing the different features such as aperture, magnification and field of view against each other.

Upland and extreme hunting The best choice here is 7x, 8x or 10x magnification and an objective lens diameter of 35-45mm.

Deer hunting The choice here depends on whether you will be in the woods or in open country. But, an 8X42 pair would make a good all-round choice, suitable for a variety of conditions.

Focusing screw Ocular lens, or eyepiece


Prism housing

KEY TO THE ICONS BK-7: Prism with normal light transmission.

N2: Nitrogen-filled binocular body prevents moisture forming on the inside of the lenses.

Waterproofing: Specifies that the binoculars are waterproof.

Case: Specifies that a case is included with the binoculars.

Field of view: Indicates in metres the breadth of the landscape visible in the binoculars at a distance of 1,000 m. In general, the higher the magnification, the narrower the field of view. Some manufacturers state the field of view in degrees, which can be converted to metres as follows: 1 degree = 17.50 meters so if the field of view is 8 degrees, that equals 140 metres (8 x 17.50).


Exit Pupil. 5,10mm

Objective lens

BaK-4: Special prism with approx. 40% better light trans­ mission than BK-7.

Twilight performance.

630 G

Weight: Specifies the weight of the binoculars.

Objective ring

Exit pupil: Designates how much light reaches the eye from the binoculars. An exit pupil of 2-3mm is sufficient in normal daylight. In low light conditions, it needs to be at least 5mm. The pupil of a person aged 30 or less will be able to expand to 7mm at most. The exit pupil is found by dividing the objective lens diameter by the magnification, e.g. 10 ÷ 42 = 4.2mm. Twilight performance: Specifies the binoculars’ performance under poor light conditions. It is calculated by multiplying the magnification by the objective lens diameter and finding the square root of the result and multiplying by 100. For 7x42 binoculars it is 175, and for 8x56 binoculars it is 212. This means that you can see at 175 m with 7x42 binoculars and out to 212 m with 8x56 binoculars.



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Exp seeland catalogue 2015  

So this year we have expanded our range considerably with a view to offering everything you need for the hunt – at high quality and great pr...

Exp seeland catalogue 2015  

So this year we have expanded our range considerably with a view to offering everything you need for the hunt – at high quality and great pr...

Profile for harkila