Do you want to buy binoculars? With a good pair of binoculars, a whole new world will literally open up for you! Below are the most important things to consider when choosing binoculars that meet your needs.
Magnification
The magnification determines how much the image is brought closer. Higher magnification is not always better. The higher the magnification, the more difficult it becomes to keep the viewer's image stable. At magnifications of 10x and above, the shaking of the hands becomes really visible. At magnifications above 12x, it becomes almost necessary to use a tripod.
At higher magnifications, the diameter of the exit pupil is smaller than at lower magnifications. This is the size of the light beam leaving the binoculars and entering the eye. The wider this beam is, the more comfortable the binoculars will be, as it is less precise how well you position the binoculars in front of your pupil. As a result, you are less likely to see black edges when looking.
The higher the magnification, the larger the binoculars become, with consequently less light output. If you use your binoculars at dusk, 8x magnification binoculars perform better than 12x magnification binoculars.
Some binoculars have adjustable magnification: you can zoom in and out. This means that the binoculars are not optimised for a particular magnification and therefore will not provide the best quality. That is why you will not find zoom binoculars in the better classes.
How much magnification is that?
In order to get a reasonable idea of how much binoculars bring the image closer, we have created the following tool. You can choose between different magnifications and there is a choice of two images.
Which magnification is suitable for which purpose?
| Magnification | Purpose | ||
|---|---|---|---|
| Low vergroting | (4x - 6x) | sports events, theatre, concerts | |
| Medium vergroting | (7x - 10x) | universal, nature observation, hunting, field sports | |
| Strong vergroting | (>10x) | astronomy, distant objects | |
Lens diameter
This diameter determines the 'light-gathering capacity' of the viewer. The larger the front lens, the more light will enter it. Now this is theoretical. By using better glass and multiple coatings, binoculars can perform better. Because of this, good but smaller binoculars can sometimes perform better than cheap, larger binoculars.
For more information regarding light performance, please refer to the Binocular Explanation
Which lens diameter for which light conditions?
| Lens diameter | Light conditions | ||
|---|---|---|---|
| Small | ( < 40mm ) | Sufficiënt light | |
| Medium | ( 40 - 50 mm ) | Universal | |
| Large | ( > 50mm ) | Twilight | |
Eye relief
Eye relief is the distance between the eyepiece (the lens of the binoculars through which you look) and the spot where the image is formed.
If you wear glasses, it is advisable to take into account adjustable eye relief. The cheapest binoculars often do not have this, which makes the eye relief for spectacle wearers too large. With most models it is possible to fold back the eye rubbers or to turn in/out the eyecups. Good eye relief is important to ensure that the light beam reaches the pupils optimally.
Choosing Roof or Porro Binoculars?
There are two types of binoculars; porro and roof prism. The difference between the two is the arrangement of the prisms.
Roof prism binoculars
In roof prism binoculars, the roof prisms (also called pentaprisms) are placed one behind the other. The light passes through the binoculars almost in a linear line. This allows this type of binocular to be more compact. A roof prism binocular is more expensive in construction than porro binoculars, but also more compact and better air-tight. The latter is because during focusing the volume of the binoculars does not change.
Porro binoculars
With porro binoculars, the image is transported via an N-shaped bend, where the prisms and the objective and eyepiece are not directly opposite each other, which is why this type is generally wider than roof prism binoculars. The advantage of this arrangement is that binoculars with porro prisms offer a little more depth perception.
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