| The use of binoculars | | | | divided by 12 is just over 4mm. A bigger exit pupil will |
| Binoculars have become very popular in recent years. | | | | do better in low light, but there are other considerations. |
| They have moved beyond military, police and | | | | A true night binocular |
| surveillance use and become a common piece of | | | | But for night time pursuits like hunting, you will need |
| equipment for recreational purposes. Beyond bird | | | | binoculars with an infra red light source to be able to |
| watching, they are increasingly being bought for use in | | | | see anything in almost total absence of light. The range |
| hunting, fishing, boating, camping, hiking, in fact they can | | | | of these light sources varies so you need to consider |
| add to the pleasure of most outdoor pursuits. | | | | what you need. They are no use for hunting if you can |
| Most of these activities take place not just in daylight | | | | only see 10 yards. |
| but at dawn and dusk or even in the night time. You | | | | Binocular types |
| see many adverts these days for night vision | | | | Secondly, there are different types of optical device |
| binoculars and they might seem like an attractive | | | | for different uses. A monocular is similar in construction |
| proposition, but not all night vision binoculars are made | | | | to a telescope. It is sometimes referred to as a |
| the same. You need to be aware of the differences | | | | spotting scope which describes what it is used for. It is |
| or you could end buying something that doesn't live up | | | | OK for scanning the terrain or the sea to spot a way |
| to your expectations or paying a lot of money for | | | | point or one of your companions. |
| functionality that you don't need. | | | | A bi-ocular has two eye pieces but only a single front |
| Low light binoculars | | | | lens. This feels more natural to use but is a |
| Firstly, there is a difference between binoculars | | | | compromise. A true night vision binocular has two front |
| designed to make the best use of very low light | | | | lenses meaning that each eye is equally adjusted to |
| conditions and a true night binocular. If you will be | | | | the night vision viewfinder. If your activity involves long |
| operating at dawn or dusk, low light binoculars could | | | | periods of use, these binoculars will feel more |
| suit your purpose. You can get an idea of how well a | | | | comfortable. |
| pair of binoculars will perform in low light from its exit | | | | So, before setting out to purchase night vision |
| pupil. This is the diameter of the beam of light as it | | | | binoculars, consider in what light conditions you will be |
| leaves the eye pieces. If you hold the binoculars at | | | | using them and whether you will be using them for |
| arms length, you can see these small circles of light in | | | | sustained periods. A true night vision binocular can set |
| each eye piece. To find the actual size of the exit pupil, | | | | you back several hundred dollars and may be a waste |
| you divide the diameter of the lenses by the | | | | of your money if they are more than you really need. |
| magnification. e.g. The binoculars are 12x50. 50mm | | | | |