Types of Binoculars
Binoculars are usually designed for a specific purpose. Models such as compact binoculars, marine binoculars, bird watching binoculars, and hunting binoculars are all handheld optics that differ greatly from spotting scopes or telescopesm which are mounted to a tripod and typically have a greater level of magnification. Depending on how you will use your binoculars will determine what type of binocular to buy. Magnification, brightness, moisture resistance and weight are all important factros to consider. A pair of binoculars that are not used because they are too heavy and clumsy may feel like a "bad" pair of binoculars. Those walking and hiking will typically prefer a small, lightweight pair of binoculars. A pair of binoculars used in a moving stance (such as on a boat) should have a lower level of magnification since it can be harder to maintain focus. Bird watching binoculars typically require a higher level of magnification because more detail and proximity is required. A spotting scope
with a higher level of magnification can be a great addition ta pair of bird watching binoculars.
Binoculars and other optics are typically expressed by two numbers. For example, 8x42. The first number refers to the level of magnification. 8x means that the optic will appear 8 times closer than it woudl to the naked eye. If you are viewing an object 100 yards away with a pair of 8x binoculars, it will appear as if it is about 12.5 yards away (100 yards divided by 8). A number such as 8-10x42 would indicate an optic that is variable and can be adjusted from 8x to 10x magnification.
Objective Lens Diameter
The objective lens, which is the lens furthest away from your eyes and closest to the object being viewed, is the second number in 8x42. It tells you teh diameter of the lens in milimeters. An 8x42 pair of binoculars woudl indicate a 42 milimeter lens objective. The diameter of the objective lenses largely determines how much light your binoculars can gather. The more light it can gather, the better you will be able to see in low light situations.
Exit pupil is a number that indicates how bright objects will appear when seen in low light scenarios. The higher the number, the brighter the image. Exit pupil is measured in milimeters and is calculated by dividing the diameter of the objective lens by the magnification. Therefore, a 8x32 binocular will have an exit pupil of 4mm. Binoculars that will be used more in dusk and dawn situations, such as hunting bincoulars, should purchase binoculars that have at least a 4mm exit pupil. For standard daylight situations, exit pupil can be ignored.
Eye relief is the distance between each eyepiece and your eyes while the maximum field of view is visible within the binocular. A long eye relief increases comfort by allowing you to hold the binoculars further away from your eyes.
Field of View
As you might expect, field of view tells you how wide of an area you are viewing (in feet), 1,000 yards from where you stand. A higher level of magnification results in a smaller field of view.
Bird Watching Binoculars
Binoculars used for bird watching come in many different shapes and designs, but are normally around 8-10 times magnification and have a lens objective between 30-45mm. They are often roof prism which make them more convenient and easier to use. This also gives them the ability to follow a bird in flight. Bird watching binoculars are usually waterproof, nitrogen -filled and rubber coated for shock-proof functionality. They are intended to be used in all conditions.
Marine Binoculars are primarily intended to be used on or around water. They usually have a magnification of 7x and a lens diameter of 50mm, which gives the binoculars a 7x50 setting. 7x magnification provides a wider field of view and a broader view of the landscape and the horizon.
Marine Binoculars are not limited to 7x50 but has versions as ranging from 10x50, 12x50, etc. The lens diameter is often 50mm or larger so that teh user can receive optimal light even at dusk or dawn.
Compact binoculars are typically used in conditions were larger, more bulkier binoculars are not appropriate, such as walking, hiking, and during sporting events.
Compact binoculars provide a picture which is similar with the larger conventional binoculars, but are a bit more limited in features. The field of view is usually a little less wide and objective lenses is usually smaller than full sized binoculars.
In all honesty, hunting binoculars are very similar to bird watching binoculars. They may have a
slightly thicker rubber ring and therefore be a bit more shock resistant and less vulnerable to careless
treatment. Hunting binoculars will also be offered in camouflage or dark green colors to blend in
with the urroundings better. Hunting binoculars are meant to be used in the woods, over fields and clearings. The magnification level varies greatly, but is usually between 7x and 12x. Hunting binoculars may have flip-up protection and are often fast focus to
quickly set. The body is often water resistant by several layers of O-rings to secure a
fog-proof and waterproof function.