Jun. 05, 2025
Why are Lens Coatings Used?
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Imagine walking through a thick forest. Sunlight struggles to penetrate the dense foliage, making it difficult to see. Similarly, light encountering and then trying to pass through a series of lenses in binoculars encounters obstacles. Here’s what happens:
Special lens coatings are applied to help combat these issues and improve the overall viewing experience through binoculars.
So with binoculars, scopes, monoculars and many other optical devices like camera lenses, anti-reflection coatings are designed to assist with light transmission thus helping to produce a sharper, brighter image with improved contrast. These days almost all good quality binoculars have some sort of anti-reflection coatings applied to at least some of the air-to-glass surfaces of their lenses.
These anti-reflection coatings are often made up of a number of incredibly thin layers, typically measured in microns (one-thousandth of a millimeter), that are deposited on the lens surface. Each has a distinct index of refraction which alters the lens’s performance with different wavelengths and at different incident angles and work by manipulating light in specific ways:
So they kind of function like a tiny “traffic cop” for light. The coating is composed of alternating layers of materials with different refractive indices (how they bend light). These layers cause incoming light to interfere with the reflected light, cancelling it out and allowing more light to pass through to your eye. Imagine two sound waves perfectly out of phase, cancelling each other out – that’s the principle at work here!
Because of this, color effects often appear at oblique angles and so you can sometimes see these coatings as they are usually what produces the blue, red, or green reflections you see when you look into the front of a binocular’s objective lens at different angles.
Improved Transmittance and Image Brightness
In any lens, some of the light that passes through the lens is reflected by the front (incident light) and rear (exiting light) surfaces. This reflection reduces the amount of light passing right through the lens and thus to your eyes.
If the amount of light reflected away is very bad, the image you see when you look through the binoculars will be darker than on binoculars that transmit more light.
As well as producing a less bright image, reflected light may cause ghosting, flares and also affect the contrast of the image.
So during the manufacturing process, these special anti-reflective coatings are added to the lenses on better quality binoculars, which drastically decreases the amount of surface reflection losses and can significantly increase the transmittance of light to ensure you get as bright, clear and sharp image as possible.
Ghost Imaging
What is more, the undesirable secondary reflections that can interfere with the transmitted image, producing what is known as “ghost imaging” can also be all but completely be eradicated using good anti-reflection coatings.
More Benefits:
Because the amount of reflection from the lenses is reduced, these coatings also help in that they reduce the glint coming off the lenses. This is important if the user of the binoculars does not want to give away their position. Important for military, law enforcement, hunting and even general wildlife observation applications.
When researching a binocular, it is important to note how the manufacturer describes their coatings:
Coated – means a single layer antireflection coating on some lens elements, usually the first and last elements (the only ones you can see).
Fully Coated – means that all air-to-glass surfaces are coated, which is obviously an improvement on a single-layer coating.
Multi-coated – means that at least some surfaces (again, usually the first and the last) have multiple layers of antireflection coatings. (A multilayer coating effectively reduces reflected light that cannot be eliminated with a single-layer coating, and increases the transmittance of light.) Multiple layers are about an order of magnitude more effective than a single layer.
Fully Multi-Coated – means that all air-to-glass surfaces have received multiple layers of anti-reflection coatings – this is what you want in your binoculars.
The table below shows Transmittance by type of coating:
Per Single Lens Surface 10 Lens & Prism Surfaces No Coating: 96% (0.96) x Power of 10 = 0.66 66% Single-Layer: 98.5% (0.985) x Power of 10 = 0.86 86% Multilayer Coating: 99.5% (0.995) x Power of 10 = 0.95 95%The specific materials used in lens coatings are a closely guarded secret by manufacturers. However, common materials include:
Applying lens coatings is a complex and precise process, often involving multiple steps:
There was a time when you would only find fully multi-coated binoculars at the top end of the market. But as production methods improved and because of the influence of the cheaper production costs from mostly Asian manufacturers, more and more binoculars were being fully multi-coated.
So because of this increased competition and better manufacturing techniques, most mid-range and even some low-cost binoculars come fully multi-coated with anti-reflection coatings. So now a bin needs far more optical features, like for example the use of ED Glass in their lenses, to even have a chance of standing out from the crowd.
Best Value Fully Multi-Coated Bins
So to help with this and to help separate the wheat from the chaff, below I have listed a few of what I consider to be some of the best value for money fully-multi-coated binoculars around:
More: View all Best Value Binoculars I have reviewed.
Beyond the core functionalities mentioned above, some manufacturers offer additional features through their lens coatings:
A Note on “Ruby Coatings”
There are some binoculars that advertise that they have ruby or red multi-coatings. These are intended to reduce glare in bright light, or enhance specific colors in specific environments and has had some limited success in very specific applications.
But due to the fact that it “looked cool”, many low-end binocular producers started making ruby-coated binoculars to filter red to compensate for their poor-quality optics that do not properly converge the color spectrum. For more: Ruby Coated Binoculars.
Anti-reflection lens coatings on binoculars play a crucial role in enhancing your viewing experience and are important to take note of when comparing instruments. By understanding how they work and the features they offer, you can make a better decision when choosing the right binoculars for your needs.
Remember:
When it comes to binoculars, one golden rule stands true: invest in the best quality you can afford. A budget pair is better than none, but you’ll always wish you’d gone for higher-quality optics. Want to know which models stand out? We’ve rounded up the best binoculars to help you find the perfect pair for your niche.
These are the two most crucial specs to consider. Magnification (the first number, e.g., 8x in 8×42) shows how much closer objects appear. Aperture (the second number, e.g., 42 in 8×42) is the lens diameter in millimeters, dictating how much light the binoculars gather. More magnification gets you closer but makes the image shakier (10x is typically the limit for hand-held use). Larger apertures enhance image quality in low light but make the device heavier and pricier. For example, binoculars with 15×70 or 25×100 are excellent for astronomy but not ideal for carrying around on a hike. For birding or nature observation, 10×42 or 8×42 are great options.
FOV determines how much of a scene you can see. It can be listed as angular (e.g., 6°) or linear (e.g., 322 ft at 1,000 yards). Lower magnifications increase FOV, making it easier to track moving targets like birds.
Your IPD is the distance between your pupils. Most binoculars range from 55-70mm, but if your IPD doesn’t align with this, the binoculars could be uncomfortable to use.
Binoculars come in two common prism designs:
Choose porro prisms for stargazing and roof prisms for outdoor activities like birding. hunting, or hiking.
Eye relief refers to the distance from your eyes to the lenses while still seeing the full image. Long eye relief (10mm or more) is essential for eyeglass wearers. Models with fold-down or removable eyecups can help if the relief distance feels short.
This is the size of the light beam that enters your eyes, calculated by dividing aperture by magnification. For daytime use or older users (whose pupils are smaller), an exit pupil of 3-5mm is usually sufficient. Nighttime applications benefit from larger exit pupils, such as 7mm.
You’ll typically find two options:
High-end binoculars come with fully multi-coated lenses, reducing glare and enhancing light transmission, especially in dim conditions. Certain glass types, like the HD or ED (extra-low dispersion) lenses, combat chromatic aberration and provide true-to-life colors.
While having bins with high-end lens coatings sounds appealing, they often yield only minor improvements for casual users. Don’t feel obligated to overspend if your needs are basic.
Materials like polycarbonate, aluminum, and magnesium impact durability, weight, and cost. Polycarbonate is cost-effective and sturdy, while magnesium offers the best mix of strength and low weight in premium models.
Advanced features like image stabilization, range-finding, or night vision can be useful for niche needs but often come with trade-offs like added weight and cost.
Today, binocular shoppers face an embarrassment of riches. Even entry-level models offer solid performance, thanks to advancements in modern manufacturing. For around $50, you can get binoculars that get the job done. Spending $300-500, however, delivers better build quality and features like fully multi-coated lenses. For enthusiasts willing to shell out $2,000 or more, high-end brands like Zeiss or Swarovski offer unparalleled image quality and precision and might feel even better than your natural eye sight.
What makes high-end binoculars from brands like Swarovski, Zeiss, and Leica so expensive? It mostly comes down to exceptional optical quality and durability. Their reputation also plays into the price. But in the world of optics, higher prices do tend to reflect higher quality. Don’t dismiss expensive options outright; their premium cost is often well justified.
That said, mid-range binoculars like the Vortex Viper HD or Nikon Monarch offer great performance too. You get 70–80% of the quality of high-end models at just a fraction of the cost.
Now, let’s break down the key features and characteristics to look for when choosing the right pair of binoculars for you.
Obviously, the biggest selling point of high-end binoculars is their premium glass, coatings, and coating technique. Their premium lenses boast edge-to-edge clarity, minimal chromatic aberration, and enhanced low-light performance. With high-end binoculars, you’ll notice every detail in a bird’s feathers or easily track wildlife like deer at dawn or dusk.
However, some argue that optical benefits diminish beyond the $1,000-$1,500 range. For example, Vortex Razor HD models, which retail for $950-1,100, compare favorably to higher-tier options, delivering excellent clarity at a fraction of the cost.
Binocular lens coatings reduce light reflection on glass surfaces, so more light passes through to your eyes and less is lost to glare. Without coatings, each glass surface can reflect up to 5% of the light, significantly dimming the image. Let’s take a basic binocular with ten glass-to-air surfaces. Without coatings, only about 50-60% of incoming light actually reaches your eye. Single-layer coatings bring this figure closer to 90%, and modern multi-coatings can increase it up to about 95%. The difference is dramatic, especially in dim lighting.
But coatings aren’t just about light or brightness. They also impact color neutrality, contrast, and resistance to glare. A well-coated surface reduces visual noise, delivers richer contrast, and corrects for color tints caused by subpar coatings.
When looking at binocular specs, pay close attention to the coating descriptions, as some brands may oversimplify or exaggerate the benefits. Terms like “multi-coated” carry little weight without clear specifications. Reputable brands will disclose precise coating details, while lesser-known models may use vague labels.
Coated – The term “coated” refers to the bare minimum – at least one glass surface in the binoculars has a single-layer anti-reflective (AR) coating. The rest of the surfaces are likely bare glass, which reflects a significant amount of light.
Fully Coated – This term suggests all glass-to-air surfaces are coated with a single layer of AR coating. While better than “coated,” prisms don’t always follow suit and may remain uncoated or inconsistently treated.
Multi-Coated – Binoculars labeled “multi-coated” feature multiple AR coatings on at least one lens surface. This does enhance light transmission, contrast, and glare reduction but the term can be misleading since not all surfaces may receive the same treatment. Frequently, the objectives or eyepieces have multi-coatings, but other surfaces may only have single coatings.
Fully Multi-Coated – This is the gold standard in consumer optics. All glass-to-air surfaces, including objectives, prisms, and eyepieces, are multi-coated with advanced AR coatings. These reduce light loss to less than 1% per surface, resulting in brighter, sharper, and more colorful images.
For more information, please visit Single layer magnesium fluoride coating.
Featured content:Prism Coatings – For prisms, the treatment varies. Porro prisms typically rely on total internal reflection (TIR) and don’t require reflective coatings. However, roof prisms often need phase-correction and dielectric coatings to enhance contrast and prevent light phase shift.
Some budget binoculars come with flashy ruby or orange-coated lenses. While they might look cool, they don’t always mean better performance. Actually, darker or greenish coatings are usually a sign of higher-quality optics because they’re designed to cut down on reflections and improve light transmission. On the other hand, those bright orange coatings can cause glare and even reduce the amount of light that makes it through the lenses. Don’t be fooled by the flashy appearance!
Ever looked through a pair of so-so binoculars and found the view blurry or lacking detail? That’s usually a result of poor-quality lens glass.
The lens glass is the central component that influences brightness, sharpness, and color fidelity. Cheap glass can create chromatic aberration – that annoying “color fringing” you see around objects – and squash fine details like plumage coloration on a bird. But with high-quality glass, those details come alive, even in dim lighting or at a distance.
Standard Optical Glass: Many entry-level binoculars use standard glass, which performs decently under average conditions but leaves plenty of room for improvement. Chromatic aberration and reduced brightness are common drawbacks in this range.
HD Glass: When a brand labels an optical instrument as “HD,” it typically refers to one of two things:
ED Glass (Extra Low Dispersion): This term that carries a more consistent meaning across brands. ED glass is designed to reduce chromatic aberration by aligning light wavelengths more accurately, thereby producing sharper, more color-accurate images. ED specifically refers to lenses that include at least one element of ED glass.
However, the effectiveness of ED lenses depends on the overall design of the optical system. Poorly engineered bins with ED glass may still produce worse results than a well-designed system without it.
Use ED and HD as indicators of quality but don’t skim on deeper research.
Another major advantage of premium binoculars? They’re built to last a lifetime. High-quality models are often crafted using resilient materials such as magnesium alloy or carbon fiber that increase durability without extra weight. Many are also waterproof, fog-proof, and generally are built to perform well in extreme, unpredictable conditions where you can accidentally bump, drop, or get under a surprise rainstorm.
In contrast, cheap binoculars often feature a plastic chassis and plastic parts – focus wheel, eyecups, and eyepiece housings. While plastics keep the price low, they do compromise resilience and overall performance. For example, focus wheels on cheaper models tend to have inconsistencies, while eyecups might rattle or fail to stay in place.
Additionally, many budget binoculars aren’t fully sealed. They might be marketed as “weather-protected,” but they’re rarely truly waterproof or fog-proof. This means dust can get into the system, and you might experience internal fogging or even mold growth on the lenses.
Warranties are something many first-time binocular buyers overlook, but they can be a major deciding factor, especially if you’re investing in a high-tier optic. Free repairs or cleanings—even decades after purchase—make brands using a “no-questions-asked” approach, such as Swarovski, Vortex and Maven, especially appealing to serious outdoor enthusiasts.
Sure, binoculars with top-notch warranties may cost more upfront, but in the long run, you’ll save serious cash on repairs, replacements, or upgrades.
If you see the term “lifetime warranty,” don’t assume it’s straightforward. Check what exactly it covers. Like we mentioned Vortex and Maven, which offer unconditional lifetime warranties. Whatever you do to your bins, they’ll repair or replace them at no cost to you. On the other hand, some brands may only cover a set number of years.
A transferable warranty means that if you sell your binoculars later, the new owner can still benefit from the warranty. This feature could seriously increase the resale value of your optics. And again, not all brands offer this. Some only extend their warranty to the original owner, with proof of purchase needed for repairs and replacements.
Does the warranty include accidental damage, or is it only for defects in manufacturing? This is an important detail to understand. Some brands, for instance, exclude water damage, even on binoculars labeled waterproof.
A good warranty is useless if claiming it feels like pulling teeth. The warranty claims can be fast and painless or slow and inconsistent. If this is a concern, check reviews from other customers to see how smoothly the claims process goes.
Are all cheap binoculars a waste of money? Definitely not. While cheap bins (below $150) can be a gamble, there are some decent options out there if you know what to look for. If you’re working with a tight budget, porro prism designs usually offer better performance for the price compared to roof prisms.
So, as a beginner shopping for your first pair of binoculars, what should you go with – cheap entry bins under $150, mid-range bins, or high-end bins over $.
Well. high-end binoculars from brands like Swarovski and other German or Japanese manufacturers are known for unmatched clarity, effortless usability, and exceptional customer support. For some people, the old saying “buy once, cry once” holds true. Investing in a premium pair means you probably won’t need to upgrade for years (or even decades).
That said, you shouldn’t feel pressured to splurge on premium binoculars right off the bat. You can start with something in the mid range like Vortex, Athlon, and Kowa which offer excellent binoculars for the money.
Prioritize Anti-Reflective Coatings
Aim for fully multi-coated optics! This coating type greatly improves light transmission and reduces glare.
Don’t Underestimate Weight and Balance
Those cumbersome budget rigs might be tempting, but after an hour in-hand, you’ll regret not paying for lightweight ergonomic models.
Check Chromatic Aberration
Before settling on non-ED glass in the sub-$300 range, check for color fringing. Look for straight edges against bright backgrounds and ensure no noticeable halo effects distract your clarity.
Be Wary of Marketing Terms
Terms like “HD glass” are often generic. Verify whether they apply exclusively to lens systems or entire prisms. Transparency from trusted optics manufacturers often correlates with more trustworthy quality.
Be Specific
To narrow down choices, consider these questions:
For varied uses like travel, events, or casual nature watching, opt for mid-sized designs like 8×32, 8×42, or 10×42. They strike a perfect balance between portability and image clarity. Look for rugged, waterproof models with long eye relief for added durability and ease of use.
The Hawke Vantage 8×42 binoculars deliver great performance at an unbeatable price under $150. With an 8×42 configuration, they strike the perfect balance between magnification and light-gathering, making them versatile for a variety of settings and lighting conditions. These binoculars are ideal for outdoor enthusiasts looking for dependable optics without overspending.
The Nikon Monarch M5 8×42 is perfect for low-light situations, like dawn or dusk, when wildlife is most active. Featuring ED (Extra-low Dispersion) glass, it reduces distortion and chromatic aberrations for sharp, clear images. The dielectric high-reflective multilayer prism coatings enhance brightness and color accuracy, making every view vivid. With comfortable turn-and-slide eyecups and long eye relief, even eyeglass wearers can enjoy extended use with ease.
The Nikon Monarch M7 10×42 is a versatile option for bird watching, hunting, or wildlife observation. It boasts an ergonomic, non-slip rubber design for comfortable handling and lightweight construction for long excursions. The multiple prism coatings enhance brightness and color, while its fog-proof and waterproof housing ensures durability in any weather.
The NL Pure 8×42 delivers simply amazing optical performance with a wide field of view and excellent sharpness almost to the edge of the frame. Despite the premium price, dedicated users report zero regrets due to the unmatched viewing experience that justifies the investment for frequent users.
Spotting wildlife calls for higher magnifications like 8x or 10x to capture fine details. Binoculars with larger apertures (above 35mm) are helpful in low-light scenarios like dawn or dusk. For birdwatching or safaris, go for rugged models like 8×42 or 10×42, which balance magnification, brightness, and weight. 8x is better for birding in forests and jungles.
The Crossfire HD 8×42 offers usable but basic optics, suitable as an entry-level birding binocular. While functional at its $150 price point, best suited for casual or beginning bird watchers on a tight budget.
This Kowa binocular stands out with its incredible field of view of 378 feet at 1,000 yards, making it ideal for tracking birds in motion. It features a 5.9-foot close focus, ED glass objectives for reduced chromatic aberration, and multi-layer anti-reflective coatings for superior clarity. The binoculars are built to handle tough conditions, with water- and dirt-repellent KR coatings, making them perfect for serious birding.
The Trinovid HD 8×42 provides excellent value at one-third the price of premium Leica models while being noticeably lighter and offering better close focus at around 5.9 feet. Though it’s not as sharp as top-tier models, the difference is not huge, making it ideal for serious birders seeking premium quality without the maximum price.
The NL Pure 10×42 offers an exceptionally wide field of view with excellent sharpness nearly to the edge of the field stop. The 10x magnification provides additional reach while maintaining the NL Pure line’s superior optical performance, making it perfect for dedicated birders who need extra magnification without sacrificing image quality.
Go with 10×42 or 10×50 binoculars that are waterproof and fogproof. If you’re considering 12×42 or 12×50, they’re a good choice if you’re mostly using them with a tripod. Otherwise, you might find the image too shaky.
The Diamondback HD offers surprising quality that compares favorably to more expensive models like the Monarch 7. Available at competitive price points, it delivers excellent value for hunters needing reliable optics without breaking the bank.
The Viper HD represents a significant upgrade from entry-level optics, providing premium features at $500. Users report substantial improvement in viewing experience over cheaper options, making it ideal for serious hunters wanting high performance without reaching for the most expensive tier.
The Vortex Razor HD 10×50 binoculars deliver exceptional optical performance with outstanding clarity, sharpness, and true-to-life color. Designed for versatility, their advanced HD optical system and larger objective lenses excel in low-light conditions, making them perfect for outdoor enthusiasts and hunters. Durable, lightweight, and built for all-weather use, these binoculars are an ideal choice for those who need reliable performance in any environment.
The VORTEX Razor UHD 12×50 binoculars offer unparalleled clarity and brightness, thanks to their premium Ultra High Definition optical system. Perfect for detailed long-range viewing, they provide enhanced edge-to-edge sharpness and vibrant color accuracy. Built with rugged durability and a lightweight magnesium chassis, they are ideal for adventurers who demand high-performance optics in all conditions.
The LaserForce 10×42 combines rangefinding precision with Nikon’s optical clarity, offering reliable distance measurement (up to 1,000+ yards). One of the best affordable rangefinding binoculars on the market.
The BX-4 Range HD features True Ballistic Range (TBR/W) technology for angled shot compensation. Its motion-activated display and Pinpoint Laser System ensure fast, accurate readings, while Leupold’s HD optical coatings deliver bright, sharp images in low light.
The Geovid R stands out with integrated ballistic compensation and class-leading optical performance, pairing Leica’s HDC/Multicoating for exceptional light transmission. Its ergonomic design and precise rangefinding (up to 2,000+ yards) make it a top choice for hunters and precision shooters.
The KOWA BDII XD Wide Angle 6×32 binoculars offer an ultra-wide field of view and outstanding clarity, making them perfect for nature observation and scenic viewing. Their XD lenses enhance image sharpness and color reproduction, delivering vivid and detailed views. Lightweight and durable.
The SWAROVSKI CL Companion 8×30 binoculars combine premium optics with a sleek, lightweight design, making them ideal for travel. They provide bright, detailed views while being easy to carry and use on long journeys.
For stargazing, aperture matters most. Larger lenses (50mm or more) gather more light, essential for dim celestial objects. Models like 10×50 are good for hand-held use, while 15×70 or 20×80 are better for tripod-mounted viewing. Prioritize binoculars with tripod compatibility and consider a parallelogram mount for extended sky-watching sessions.
The Diamondback HD 15×56 offers high magnification and light-gathering capability at a budget-friendly price. The model delivers solid optical performance for its price, backed by Vortex’s lifetime warranty, making it a practical choice for entry-level astronomy or distant terrestrial viewing.
The BX-5 Santiam HD 15×56 delivers exceptional optical clarity and brightness, outperforming competitors in sharpness and detail resolution. Its robust build quality and advanced low-light coatings make it ideal for hunters and astronomers needing reliable performance in challenging conditions.
The SLC 15×56 proves itself as the best big glass available with superior light-gathering ability that particularly shines during dusk observations. Built to last a lifetime, these binoculars excel at long-distance viewing across challenging terrain, making them the ultimate choice for serious astronomers and long-range observers despite their premium price.
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