Binoculars are an indispensable tool in a wide range of activities including birdwatching, hunting and stargazing. With a bewildering array of different models on the market, choosing the right one can be overwhelming. All binoculars magnify objects, but not at the same level or clarity. The optimal binoculars for one activity may be entirely unsuitable for use in a different activity. The technical specifications of binoculars seem complicated, but with a basic understanding of their meaning, choosing the right pair will be a stress free task.
Magnification Strength and Binoculars
One of the most important aspects to understand about binoculars before purchasing one is the magnification capabilities. The magnification strength of binoculars is denoted by a number or numbers followed by the letter x. The number refers to the enlargement factor. A magnification of 2x means the binoculars make an object appear twice as large as it would appear without using them. The higher the number, the larger the object appears. Larger magnifications are more susceptible to shakiness making them unsuitable if the binoculars are to be handheld. Using a tripod helps minimize shakiness so the image appears more stable.
More than one number preceding the x means the binoculars are capable of multiple magnification strengths. It is important to note there are two types of binoculars with this feature with both producing very different results. Zoom binoculars have two numbers with a dash between them which denotes the range of magnification capability. A slash between the numbers indicates the binoculars can switch magnification back and forth from one number to the other one. Zoom binoculars tend to have a smaller field of view compared to binoculars with fixed magnifications.
The Objective Lenses and Field of View in Binoculars
The number following the x refers to the diameter of the objective lenses. These lenses, measured in millimeters, are positioned at the far end of the binoculars away from the eyepieces. Larger lenses allow more light in making objects appear brighter so that more details are visible. Larger lenses are ideal to use in low light situations. Larger lenses also increase the overall size and weight of binoculars. To prevent hand fatigue and image instability, heavier binoculars may require using a tripod to ensure stability.
The field of view describes the extent of the area visible through the binoculars at a distance of one thousand yards. In general, a wide field of view is associated with lower magnifications. The field of view is sometimes listed in angular degrees. Each angular degree equals 52.5 feet. To determine the size of the field of view in feet, multiply 52.5 with the degree number. Some manufacturers list the field of view in feet instead of degrees. To determine the angular degree of a pair of binoculars, divide the number of feet by 52.5.
Binocular Prisms and How They Work
Besides the objective lens and the glass of the eyepieces, binoculars contain prisms. The prisms are positioned to reflect the light that enters through the objective lens so that the image seen through the eyepiece does not appear inverted. Light enters through the objective lens traveling in a straight line. So light from the bottom of the field of view travels upward while light from the top of the field of view travels downward after entering the lens. The end result causes the image to be projected reversed and upside down. The prisms correct this so that the image appears normal. The inverted image appears on the first prism which then reflects it onto the second so that it appears upright when viewed through the eyepiece.
Binoculars have either porro prisms or roof prisms. Porro prisms reflect all light that enters them. The positioning of the prisms means the objective lenses and the eyepieces are not directly in line with each other. This makes the body of the binoculars larger than those with roof prisms. Porro prisms are described as BAK-4 or BK-7. BAK-4 prisms are made from barium crown glass while BK-7 prisms are made from borosilicate glass. BAK-4 prisms are considered higher quality because they allow more light in forming a brighter image.
Roof prisms are not completely reflective so manufacturers must use technology to adjust the prisms to compensate. This makes the prisms more susceptible to aberrations that might distort the image. However, unlike porro prisms, roof prisms can be positioned in a way that minimizes the space they take up. The objective lenses and eyepieces are in line allowing for a more compact size. Manufacturers can also add special coatings to the lenses to reflect more light or ensure vivid colors in the image. Check the individual specifications of the binoculars to see which, if any, coatings have been applied.
What Makes Binoculars Waterproof or Fog Proof
Dust seeping into the barrels of the binoculars can scratch lenses, obstruct the prisms, and, overall, hamper the viewing capabilities. Moisture inside the binoculars can cause internal fogging and even grow mold over time. Manufacturers use O-ring seals to keep dust and moisture away from the internal parts of binoculars. That is what it means when binoculars are described as waterproof. However, binoculars designated as waterproof are not considered fog proof unless specified by the manufacturer.
Fog occurs on glass when there are substantial differences in temperature between the air on each side of the glass. Any moisture in the air is drawn to the cold glass causing it to fog. Which side of the glass fogs depends on which is the coldest side. Taking binoculars out of the warm house into the cold snowy outdoors to look for winter birds may cause the lenses to fog on the outside. A quick wipe with a soft cloth easily eliminates the fog so the bird watching can continue without interruption. Taking binoculars out of an air conditioned vehicle into warmer, humid air can cause the lenses to fog on the inside. The fog then has to dissipate on its own which, depending on conditions, might take anywhere from a few minutes to several hours significantly affecting activities.
The O-rings should keep out moisture and prevent internal fogging, unless they are damaged or poorly inserted. To prevent internal fogging, manufacturers remove the oxygen from inside the binoculars and replace it with argon or nitrogen gas in a process called purging. Argon and nitrogen are inert gases which do not react to temperature changes by allowing moisture to condense and fog up the inside of lenses. Nitrogen is less expensive than argon, but argon has a higher mass with makes it less susceptible to leaking if the O-rings became damaged. Both methods are effective in preventing internal fogging.
Eyeglasses and Binoculars
The eye relief, measured in millimeters, indicates the distance a person can hold the binoculars away from the eyes without the field of view diminishing. The lower the number, the closer the eyes must be to the eyepiece. For people who wear eyeglasses, a low eye relief number could interfere in their ability to use the binoculars. Binoculars with an eye relief number of 14 mm or higher work well with eyeglasses. The right binoculars can turn an enjoyable activity such as birdwatching into an outstanding experience.
Binoculars for Birdwatching
Binoculars are a must-have tool for birdwatchers. The ideal binoculars for this activity will provide the user with a wide field of view. A field of view anywhere between 330 and 450 feet provides a generous area to find birds in. Too narrow of a view makes it difficult to track quickly moving or flying birds. A magnification of 7x or 8x allows users to spot birds even in wooded areas. Larger magnification binoculars would require a tripod for stabilization eliminating the ease of movement offered with the lower magnification handheld ones. For all weather birdwatching, waterproof binoculars with antifogging features are preferable. There are numerous binoculars suitable for birdwatching available in a wide range of prices.
The Minox 62193 binoculars are priced in the higher range. However, these German made binoculars work great in a number of different activities. Birdwatchers will find the lightweight construction to be a plus. The 8x magnification puts it in the ideal range for spotting birds. The objective lens diameter of 43 mm lets lot of light in. The binoculars use apochromatic lens technology to reduce color aberrations for a crisper image. The eyecups have four different possible positions easily accommodating eye glasses.
For all weather birdwatching, the Vortex Optics Viper HD offers exceptional quality. These are mid-priced binoculars. The binoculars have a magnification of 8x and objective lens size of 42 mm. Made in Japan, these binoculars use roof prisms making them easy to hold. The lenses are coated to maximize light. The prisms have dielectric coatings which increase the reflective capability of the prism surface. The waterproof binoculars are argon purged for protection from internal fogging. Eyeglass wearers will appreciate the twist eyecups. As an added bonus, Vortex Optics includes an unconditional repair or replace warranty for the life of the binoculars.
For affordability and quality, the Polaris Optics Wideviews binoculars boasts of an extra wide field of view of 430 feet. They have a magnification of 8x with 42 mm objective lenses. Coatings of the prisms and lenses improve color accuracy while minimizing loss of light. They are waterproof and use nitrogen to make them fog proof too. The twist eyecups mean even eyeglass wearers can use the binoculars comfortably. The covers for the objective lenses remain attached to the body so there is no worry of losing them. Weighing less than two pounds, these compact binoculars offers hours of birdwatching without hand fatigue. These binoculars are great value.
The Carson 3D Series Binoculars use extra low dispersion glass for the brightest possible images even in low light. The 8x magnification brings the birds up close while the 42 mm objective lenses ensure plenty of light to see them by. The 341 feet field of view offers plenty of space to spot birds in. The eye cups are twist down so that eyeglass wearers can adjust them as needed. They are waterproofed and fog proofed using O-rings and nitrogen purging.
The Nikon 7238 Action Ex Extreme All Terrain Binoculars retail are reasonably price. The 8x magnification coupled with 40 mm objective lenses provide bright images with up close clarity. The 430 feet wide field of view provides ample room to spot birds. The 17.2 mm eye relief pairs well with eyeglass wearers. The binoculars have BAK-4 roof prisms for top of the line images. They are waterproof and also fog proof. The binoculars can be easily attached to a tripod making them great for stationary birdwatching or hunting positions.
The inexpensive NOCOEX HD binoculars are compact to fold up for easy carrying. The have a magnification of 8x and 42 mm objective lenses. It has a 331 feet field of view. The BAK-4 prisms and coated lenses work together to ensure true to life color and clarity. The eye relief is 18 mm making it easy to use for people wearing eyeglasses or sunglasses. The binoculars have O-ring seals for waterproofing. They are also fog proof making them the go anywhere, any weather binoculars.
Binoculars for Hunting
Hunters often find binoculars a useful aid in tracking prey. When purchasing binoculars for hunting, keep in mind how much natural light there will be. The brightness of the image depends on how much light can enter the objective lenses. For use during daylight conditions, objective lenses 40 mm to 42 mm are sufficient. For low light nighttime hunts, 50 mm to 56 mm in size lenses work better. Fog proof and waterproof lenses are a preferable. A magnification of 8x should work well in most conditions. Consider making sure to add a strap to the binoculars, if they do not already have one, so that there is no need to waste time stowing them after spotting the prey. Binocular harnesses are an alternative to the traditional strap. The harness wraps around the upper body, distributing the weight away from the neck while holding the binoculars more securely. Hunters have a wide range of binoculars to choose from.
Swarovski EL Range are known for their top of the line quality. The Swarovski EL Range binoculars continue the tradition with superb optics. The binoculars feature high definition glass treated with fluoride to prevent color fringing. With 42 mm objective lenses and 8x magnification, the binoculars have a field of view of 412 feet. They are water proof and fog proofed using nitrogen purging. Also included is a built in laser rangefinder. The rangefinder has a LCD display with aiming circle and can measure distances from 33 to 1500 yards which helps when sighting deer.
The Tract Toric Binoculars retail are in the mid-price range. They have an 8x magnifications and 42 mm objective lenses great for hunting in low light. They have a 377 feet wide field of view. The 19 mm eye relief is more than enough to suit most eyeglasses. The prisms use dielectric and phase correction coatings to improve the optics. The lenses are also scratch resistance so they travel in all types of terrain without worrying about taking them in the brush.
The Bushnell Legend Ultra HD Binoculars provide superior quality for a price that won’t blow the budget. The Bushnell Legend Ultra sports a 10x magnification coupled with 42 mm objective lenses and a field of view of 340 feet. The twist up eyecups are suitable for eyeglass wearers. The binoculars use roof prisms and extra low dispersion glass to minimize the chromatic aberrations. The lenses also have a special anti-reflection coating ensuring that light travels where it needs to. The lenses also have a permanent coating of Rainguard to repel water off of the outer sides of the lenses so rain won’t interfere in the hunt. The camouflage design on the binoculars make them great hunting gear.
The Vortex Optics Diamondback binoculars offer quality and affordability in one package. These binoculars feature a magnification of 10x and 42 mm objective lenses. The eye relief is a comfortable 15 mm. The lenses are coated for maximum effectiveness in even low light situations. The roof prisms are also coated to maintain true to life colors. The binoculars use O-rings and argon purging to keep the lenses water and fog free great for all season hunting.
The value priced BNISE High Powered Magnification Binoculars have a magnification of 10x and 42 mm objective lenses. The field of view is 303 feet. The optics are top quality with BAK-4 roof prisms complete with phase correcting and multi-coated optics. It is waterproof and has been nitrogen purged to make it fog free internally. The binoculars are small enough to fit into a shirt pocket for easy carrying.
The QUNSE Traveler HD binoculars are affordable for hunters of all budgets. They have an 8x magnification with 42 mm objective lenses. The field of view is 341 feet wide. The binoculars have BAK-4 prisms and coated lenses. The eye relief is 17 mm. The binoculars are waterproof and fog resistant. They are compact enough to travel just about anywhere.
Night time hunters will appreciate the Bushell 260501 Equinox Night Vision Binoculars. The binoculars offer a 4x magnification and sport 50 mm objective lenses. It is versatile enough to use during the daytime and nighttime. It uses infrared illumination to see with. It is also capable of recording video and capturing images from the binoculars. They are water resistant and compatibly with tripods.
The Night Owl Pro Nexgen Night Vision binoculars retail are priced in the mid-range. They have a 3x magnification and 42 mm objective lenses. The field of view is 70 feet at a distance of 200 feet. The binoculars have infrared illumination that can be used in total darkness situations. It uses a 3-volt lithium battery which generally lasts from 40 to 80 hours. A low batter indicator is built into the binoculars.
Binoculars for Stargazing
Binoculars provide a great way for amateur astronomers to get started stargazing. Beginners often find it easier to spot objects in the night sky using both eyes looking through a simple pair of binoculars and then later progress to using a telescope. Due to the low light conditions, binoculars for astronomical use need large objective lenses to enable as much light as possible to enter in. If the binoculars are to be handheld, then the magnification should be no stronger than 10x. The stationary nature of stargazing makes using a tripod quite convenient. Stronger magnifications than 10x can be used with a tripod, however, keep in mind that could limit the field of view. A wide field of view is necessary for identifying constellations particularly for the beginner still learning to navigate the night sky. The types of binoculars suitable for stargazing is nearly as numerous as there are stars in the night sky.
For the closest thing to using a telescope with two eyes, look no further than the Vixen Optics 1420 binoculars. The binoculars have a magnification of 40x and 80 mm objective lenses. The field of view is 136 feet. It can focus in on objects as close as 79 feet. The eye relief adjusts between 15 mm and 22 mm. The binoculars have been nitrogen purged so fog will not get in the way of seeing the stars. The large size of the binoculars would make it impossible to hold, so the Vixen Optics device comes equipped with a wood tripod. The tripod can be tilted and swiveled using a guide handle. The tripod allows the binoculars to swivel vertically by 90 degrees. The binoculars with tripod weigh 27 pounds. The tripod folds down to 39” in length.
The Nikon 7536 Premier has premium features to match the high end price. The 10x magnification is the strongest for handheld binoculars without image stabilization. The binoculars have 42 mm objective lenses and a 314 field of view. The body is made of magnesium alloy. At under three pounds, they are light weight enough make them easy to carry. It has adjustable eyecups specially designed for use with eyeglasses. The prisms have phase correction coatings. The binoculars have been sealed with O-rings and purged with nitrogen ensuring they are waterproof and fog proof. The rubber armor ensures that a person can maintain a firm hold on them even in the rain. Nikon guarantees the binoculars with a 25 year limited warranty that includes repairing or replacing the binoculars regardless of how they were damaged.
The BARSKA Blueline Jumbo binoculars have some out of this world features. It has interchangeable eyepieces giving it magnifications of 20x and 40x. The objective lenses are 100 mm in size letting in tons of light. The binoculars use multi-coated optics and BAK-4 prisms for enhancing the clarity. The eye relief varies between 23 and 18 mm depending on which eyepiece is being used. The eyepieces can be focused individually. The binoculars weigh 17 pounds. Fortunately, these binoculars are compatible with tripods which are sold separately. The binoculars can be mounted on a tripod from a bottom position or a side position. It also comes with a foam lined, hard carrying case designed to keep the binoculars protected when not in use. They are waterproof and fog proof. These binoculars are ideal not just for astronomical viewing, but also for long range observation on land such as coastal viewing of birds and whales.
The mid-priced Orion 9326 Giant View Astronomy binoculars have a magnification of 25x and 100 mm sized objective lenses. They have fully coated BAK-4 prisms and lenses for optimum clarity in images. The eye relief sits at 18 mm. Due to the size of the barrels, they are reinforced inside to ensure they maintain their structural rigidity and that the optics stay aligned no matter how many times they binoculars are moved around. The binoculars weigh 10 pounds and tripods are recommended, but not included, for use with them.
The Celestron 71370 Granite Binoculars are priced at $350. They have an 8x magnification and 42 mm objective lenses. The extra wide field of view of 426 feet is particularly helpful when searching out the constellations. The 17 mm eye relief means the binoculars are eyeglass friendly. The binoculars combine lenses coatings with phase coated BAK-4 prisms to form the sharpest images possible. The binoculars are waterproof and nitrogen purged fog proof for all temperature stargazing.
The Celestron 72022 SkyMaster DX Binoculars offer great value for a low price. The large 56 mm objective lenses work great with the low light nighttime sky. The 8x magnification is great for spotting the constellations or even distant objects on earth like flocks of birds. The nitrogen purged binoculars will not fog up internally and are waterproof too. The eyecups twist up allowing users to find the most comfortable position for their eyes even while wearing glasses. The binoculars have BAK-4 prisms and uses different coatings to achieve superior images. Celestron provides the binoculars with a limited lifetime, no fault warranty.
The Orion 09332 Scenix binoculars are an inexpensive way to start gazing at the stars. They have a magnification of 7x and a field of view of 7.1 degrees or 372 feet. The 50 mm objective lenses let in lots of light for brighter images. The binoculars have BAK-4 porro prisms for precision viewing. The lenses are coated for maximum color clarity and light. These binoculars are capable of being mounted on a tripod for hands free viewing. They are also great for birdwatching and hunting too.
Binoculars for Mariners
Marine binoculars serve a multitude of purposes. Boaters use binoculars to help spot buoys, markers and other boats. They also use them to help keep an eye on the weather. They use them to look for fish, whales, and even birds. Boats are constantly in motion, so binoculars for marine use should have a lower magnification otherwise the image will be too jumpy. A magnification of 7x is typically the maximum strength for use on boats without using binoculars with built in image stabilization. Marine binoculars need to be waterproof. Areas around bodies of water generally have higher humidity which can cause the lenses to fog, so binoculars with internal fog prevention measures are necessary. Some marine binoculars come equipped with compasses. Specially designed floating straps are available in case the binoculars accidentally fall into the water.
The Canon binoculars are specially designed for use on boats. These binoculars deliver with a variety of features. They have a 10x magnification with 42 mm size objective lenses. The lenses have low dispersion glass to combat color fringing. The binoculars are waterproof. Most importantly, the binoculars have image stabilization built into them so no matter how choppy the water is, the image won’t be too.
The Nikon 8208 Oceanpro have a 7x magnification and 50 mm objective lenses. The generous field of view of 378 feet makes spotting channel markers or whales easy. These binoculars include BAK-4 prisms and lens coatings designed to improve the performance. They are waterproof and as fog proofed. The built in compass means you never need to worry about getting lost again.
The Steiner Marine binoculars retail in the mid-price range. They have a 7x magnification and 50 mm objective lenses. The 20 mm eye relief allows for eyeglass wearers to easily use them. The BAK-4 prisms plus the optical surface coatings help light to enter the binoculars for clearer, brighter images. The sturdy body is waterproof and rugged enough to take a few drops without damage. These binoculars come equipped with an autofocus system that minimizes the frustration of not knowing what is on the horizon.
The Bushnell Marine Binoculars offer an array of features without a hefty price tag. The 7x magnification binoculars are moderately priced. With 50 mm objective lenses and BAK-4 prisms, these binoculars provide high quality optics. The hermetically sealed binoculars are waterproof, resistant to corrosion from salt water exposure and float if dropped in the water. As an added plus, the binoculars include a 3 axis, built in digital compass.
The Hooway binoculars are an affordable tool for boaters. They have a 7x magnification and 50 mm objective lenses. The field of view is 380 feet. The eye relief is at a very comfortable 22 mm. They are waterproof and fog proofed with nitrogen purging. The BAK-4 prisms provide quality optics. The binoculars float if dropped in the water. For added functionality on the water, they include a compass and an internal rangefinder which are great for boating trips.
Other Uses for Binoculars
Binoculars are great for use on nature hikes or while camping to watch animals while keeping a safe distance away from them. The ideal binoculars should have a wide field of view, around 7x or 8x magnification, and be small and light enough to carry without sacrificing quality of image. These type of binoculars also would be ideal for use at sporting events such as football or basketball games. Binoculars for children should be waterproof, lightweight, and durable. A magnification of 6x or 7x should be sufficient.
For watching wildlife up close while remaining a safe distance away, it is hard to beat the Vortex Optics Razor HD binoculars. These higher end priced binoculars have 42 mm objective lenses and a magnification of 10x. With a field of view of 362 feet, wildlife will never seem out of sight. The binoculars use roof prisms combining quality optics with an easy to handle body. O-rings seal the binoculars keeping dust and moisture out. They are compatible with most tripods. Vortex Optics offers an unconditional lifetime warranty.
The Vanguard Endeavor ED II binoculars offer premium features at an affordable price. They have a magnification of 8x along with 42 mm objective lenses. The field of view of 377 feet provides a wide area for wildlife watching. The 19.5 mm eye relief works well with most eyeglasses. The premium lenses boast a light transmission rate of 93%. Added with the anti-reflection coatings on the lenses and that means exceptional brightness of images. The Vanguard Endeavor uses O-rings to seal out water and dust and nitrogen purging for additional protection from moisture.
The Nikon Monarch 5 binoculars have an 8x magnification and 42 mm objective lenses. The 330 feet field of view is just great for watching the local wildlife. The lenses are coated for optimum color and light. The body has a waterproof rubber coating so a little rain won’t keep the binoculars from use. They are fog proof as well. The lens covers are flip down so there is no worry of losing one while on a hike.
The Athlon 113004 Midas uses dielectric coatings on the prisms to increase the amount of light reaches the user. The prisms have phase correcting coatings so that colors are more true to life. The binoculars have an 8x magnification along with 42 mm objective lenses. The field of view is an extra wide 426 feet. The eye relief of 17 mm works perfectly for eyeglass wearers. The binoculars use extra low dispersion glass to minimize chromatic fringing. They are waterproof and fog proof using argon purging.
The Vanguard Orros 8420 offer a great view for an unbeatable price. The binoculars come with a magnification of 8x and has 42 mm objective lenses. They have high quality BAK-4 prisms. The lenses have multiple coatings to facilitate great images. They are fog proof and waterproof. Weighing only 1.8 pounds and measuring 7 inches by 6 inches, the binoculars are small enough to carry on a hike or to the local football game.
Binoculars for Children
The Polaris Optics WingCatcher are compact enough to fit in children’s hands as well as work for a variety of adult activities. They have a magnification of 8x and 42 mm objective lenses. The field of view is 430 feet more than enough to view a football game, outdoor play, or locate an imaginary friend. The 17 mm eye relief is just right for people with eyeglasses. It has a roof prism and is coated for light quality. The binoculars are waterproof and fog proof so weather changes won’t interrupt any fun activities with them.
For another great Polaris Optics option, the Spectator offers wonderful performance for a great price. The binoculars have an 8x magnification and 32 mm objective lenses. They are pocket sized which makes them great for children on the go. The small size fits easily in children’s hands. They have a field of view of 362 feet. They have twist up eyecups for even children with eyeglasses will find them easy to manage. They are not waterproof or fog proof, but are adaptable to use with a tripod.
The Leupold Yosemite Binoculars sport a budget friendly price tag. They have an 8x magnification and 30 mm objective lenses. They can focus on objects as close as 10 feet. The porro prisms provide clear images. The eyecups twist up for versatility. The binoculars are waterproof. They are durable enough to handle some rough play while still delivering good images.
The Gskyer binoculars are an affordable investment for the parent who wants to introduce their child to real binoculars instead of plastic toys. They have a 7x magnification. The 50 mm objective lenses might make the binoculars too heavy for smaller children to use. These binoculars use BAK-4 prisms and have full lens coatings to improve light quality in the barrel. They are waterproof and fog proof. The binoculars come equipped with rugged rubber armor that also serves as a no-slip grip great for when children use them.
There are as many types of binoculars as there are possible uses for them. With the wide array of styles and features available, the right binoculars can be found to fit any budget. Binoculars don’t just magnify the world; they magnify the fun too.