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Best Marine Binoculars For Boating

How to choose marine binoculars


A guide to marine binoculars

This simple guide will help you pick the right pair of marine binoculars for you and your boat. You'll learn exactly what the numbers mean e.g. 7x50, 10x50, etc. and what unique features are specific and important to binoculars that will be used in a boating environment.

Binocular Numbers


Understanding the numbers on a binocular

The first number on binoculars

Every pair of binoculars comes rated with two numbers for example 7x50 or 8x30 and others but what do they mean? It's easy to understand once you know. The first number is the level of magnification so, if the rating is 7x50 then the image that you will see through the binoculars is seven times larger than what you would see with your naked eye. It's that easy.

The second number on binoculars

The second number refers to what is called the objective lens. The term objective lens just means the bigger lenses on your set of binoculars, the lenses that face the object you are looking at, not the ones you put to your eyes. The number tells you how big the lenses are, their physical size. So if your field glasses are 7x50 then the bigger lenses will be 50 millimeters in diameter. But why is the size of the lenses important? Don't we just need to know the magnification size? Well yes and no, let me explain.

Inside Binoculars


Bigger lenses mean more light

It's not just about magnification

When it comes to choosing the best binoculars it's not all about the magnification strength. If you're looking at something like a navigational buoy or a harbor entrance, it might be magnified perfectly but if it's too dark then you won't be able to see it no matter how big the image in your lens is. So the second number is just as important as the first number but for different reasons. Each plays a critical role in seeing what you are trying to see. Here's a simple way to remember it:

The larger the second number = the bigger the lenses = more light (a brighter image)

So bigger is better, right? All you need to do is buy a set of binoculars with a big first number, a big magnification, and a bigger second number so that the image is bright and clear. Nope. There needs to be a balance so let's consider the factors that go into choosing the right size binoculars for you and your needs.

Bigger is not always better


Bigger lenses doesn't always mean a brighter image

A bigger objective lens number, the second number e.g. the 50 in a set of binoculars rated 7x50, does not always mean a brighter image. Why? Because even though you might have big, light gathering lenses on the front, increased magnification in the lenses on the back decrease the amount of light transmitted to your eye. Here's a rule to help you remember it:

More magnification = Less light

More light, meaning a brighter image, is extremely important, especially at dusk, early morning or when there is little ambient light to gather such as on a cloudy day.

OK, decision made then, you need a pair of marine binoculars that have a big magnification but that deliver an image that is still bright enough to still see. Wrong. There are other factors to consider, factors that are unique to a boat.

Boats & Binoculars


Binoculars on a boat

The difference between selecting a pair of binoculars for use on land versus for use in a marine environment starts with choosing the right magnification. The higher or more powerful the magnification the more unsteady the image is going to be and boats tend to move about quite a bit. Trying to locate and then hold a steady lock on an a highly magnified image while the seas are heaving and the boat is rocking is impossible so, nearly all experienced boaters agree that a magnification of seven is perfect. 7 = Heaven.

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Field of Vision


Field of view

Being aware of what's happening around you is of paramount importance on a boat. You have to be aware of obstructions and hazards as well as other boats. The first time I sailed into San Diego it was a rough weather day, there were lots of boats out, quite a few hull-smashing Navy destroyers and a few, mammoth cruise line ships to boot. I was unfamiliar with the harbor so, with keeping the boat on course while avoiding the other ships and finding the navigational buoys, I had my hands full. Fortunately I have the right pair of binoculars and they allowed me to spot the numbers on the side of the buoys while still giving me a wide enough view that I could also see the boats around me.

Remember that sometimes you might be scanning the water through your eyepieces for an extended period of time while you search for a channel marker so a wide field of vision is definitely preferable.

Marine Binocular Review

The importance of marine binoculars


Why are bincoulars important on a boat?

Before we take a look at the other important characteristics that you will want to consider before you purchase your binoculars, let's discuss why binoculars are important to have on a boat. The most common use for binoculars on a boat is probably navigation, spotting channel markers, buoys and shore based landmarks. Knowing where you are at, especially in unfamiliar waters, will keep you from getting lost.

But binoculars are also an important piece of safety equipment too. Reefs, wrecks and obstructions floating in the water can wreck your boat faster than you want to believe and it happens more often that you might think. Sunken logs and other floating debris can breach your hull or snap off your rudder even in waters you know very well so being able to spot these things before you hit them is vital.

Lastly, binoculars are absolutely essential in the even of a man overboard situation. Being able to stay in visual contact with the person in the water is critical to saving their life.


Is fixed or variable focus better?

Variable focus

That little wheel that you sometimes see in the middle or on top of binoculars is the knob that allows you to adjust their variable focus which is sometimes called free focus. Most old sea dogs agree that variable focus is a distraction that can cause disaster. It's an outdated technology and is not a desirable feature for marine binoculars. Quite often, as he either holds on, works the tiller or adjusts the sheets, a sailor doesn't have two hands free to both hold the binoculars and work the variable focus ring.

Fixed focus binoculars

What is the difference between fixed focus and variable focus binoculars? Simply put, with variable focus binoculars you have to manually adjust them to keep an object in focus but with a set of fixed focus binoculars you don't have to adjust them at all. Fixed focus is far superior for the boater because it means you can quickly raise the binoculars for a look and then get immediately back navigating or running your ship.


Waterproof Binoculars are essential

Sure you'll be careful, but your binoculars are still going to get, that I promise you. Boating is a wet endeavor, it's just an inescapable fact so under NO circumstances should you purchase non-waterproof binoculars. Another thing you should definitely do is make sure they float if (and when) you accidentally drop them overboard. Seeing your spyglasses plummet to the bottom of the ocean is never something that puts you in a good mood and is an expensive mistake that is easy to avoid. My on own binoculars (same as the ones in the photo above) have a buoyant neck strap that is both extremely comfortable to wear and keeps my binoculars at the surface in the event of an unexpected 'water landing'.

Who said that?


Anti-fogging binoculars

Binoculars can fog up like a car windscreen on a rainy day and when they do you won't be able to see a thing. This highly dangerous scenario is the most common problem with marine binoculars but it is avoidable. Remember two things:

1) NEVER buy any pair of binoculars, no matter how great a deal you are getting, that don't have anti fogging. You may hear boaters talking about "dry nitrogen". It sounds fancy and high-tech but don't be intimidated because it really just refers to marine binoculars being filled with dry nitrogen as a means of preventing fogging.

2) Waterproof doe NOT mean fogproof.

You will drop them


Shock-resistant binoculars

Slips and falls are common on boats so it's in your own best interest to protect your purchase by making sure that the binoculars you buy are shock resistant and rugged. Binoculars are heavy and, in the wet-slick environment of a boat, can become very slippery if they aren't covered in the right material. A thick, rubber casing is best and it also makes them more comfortable to hold onto in both hot and cold conditions. This rubber coating has the added benefit of making sure that they stay where you put them and don't slide across the boat.

Internal compass


Binoculars with a built-in compass

One of the most valuable features of my own marine binoculars is their built in compass. The ability to quickly snatch a look at an object while simultaneously taking a compass bearing makes life so much easier and stress free. The alternative is to use one hand on the tiller, one hand for the binoculars and one hand on the hand bearing compass, which usually leaves me a hand or two short.

And it's not just about convenience either. The ability to take a bearing while looking at the subject through the binoculars dramatically increases the accuracy of your navigation. Being off by just a few degrees can mean serious consequences.

Know your distance


Binoculars with built-in range finders

I admit that I wasn't too excited about the range finder function on my binoculars until I started using it. Boy is it a handy little tool! It's a simple enough device to use, you just take the known height of a landmark you are looking at and then divide it against the graph you see in the eyepiece. It works very much like an unobtrusive HUD (Heads Up Display) on a fighter jet and can really be useful for determining your distance from shore or to an object.

My recommendation


The best marine binoculars

I only ever recommend things that I have used myself and have direct experience with so, after several years of using the Vanguard Marine Binoculars, I cannot praise them enough. These 7x50 binoculars are ruggedly constructed, armored with a shock-resistant rubber casing. They are both waterproof and 100% fog proof. They have the most valuable navigational aides including a built-in compass with a red, night vision friendly compass light as well as an internal range finder. Watertight up to five meters but with it's slip resistant skin and floating neck strap I will never have to test that.

I regularly shop marine binoculars to compare the latest releases with what I have and, to date, nothing else even comes close, especially for the price. Hope this guide helped you pick the right pair for you. Happy boating!

The best boating binoculars

Useful or Not?

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2012 Dale Anderson


Dale Anderson (author) from The High Seas on September 20, 2020:

Thanks Devika, glad you enjoyed it. I wrote that article because so many boaters have no idea about binoculars at all and I wanted to help them clear up a few misunderstandings.

Devika Primić from Dubrovnik, Croatia on September 20, 2020:

Informative and useful hub. Binoculars are useful when you can have a good view out at sea. It is never too late to learn about binoculars and you shared a great write up on binoculars that you are satisfied with.

Dale Anderson (author) from The High Seas on May 24, 2019:

Patricia I'm glad you liked it. I've tried a lot of different types and sets of binoculars and I can attest that finding the right ones for you is a joy. I love mine and I appreciate them every time I use them.

Patricia Scott from North Central Florida on May 17, 2019:

Thanks for sharing this I sure wish I had known this years ago when I spent so much time boating Angels are on the way this afternoon ps

Dale Anderson (author) from The High Seas on May 23, 2018:

THANK YOU so very much! As a full time boater and live aboard, I put a lot of thought and research into choosing my own binoculars so I thought I would pass on what I learned.

Kenna McHugh from Northern California on May 22, 2018:


This is a thorough article on binoculars. I knew some key points before I read this article. I checked and you covered them well.

Dale Anderson (author) from The High Seas on September 03, 2017:

Glad you found it interesting, Peggy. I get questions from sailors / boaters about it quite often as everyone has an opinion but deciding which binoculars are best for you always starts with the basic facts.

Peggy Woods from Houston, Texas on September 01, 2017:

I voted yes in your poll and found this to be very interesting. I doubt that I will ever have need of binoculars for boating but who knows what the future may bring. You made some very good points in describing what is most optimum.

Dale Anderson (author) from The High Seas on February 03, 2015:

You should probably buy binoculars anyway. If you are like my wife, she likes to spy on the neighbors.....yep I'm guna be in trouble when she reads this.

Vespa Woolf from Peru, South America on February 02, 2015:

I can see you really know your stuff when it comes to binoculars! I´m not I the market for them right now, but I thought it was interesting that the more light enters in through the lens, the better. Thank you for this useful information.

Dale Anderson (author) from The High Seas on September 14, 2012:

Thank Poseidon for waterproof binoculars! Mine have been doused by boarding waves more times than I can count. Thanks for reading.

Elena from London, UK on September 14, 2012:

Interesting to read. I wish I knew this years ago. There was a place I worked - Greenwich Quay. Every so often, big boats would dock? there. One day "The World - Luxury boat" came by - massive boat. (Awesome view out the window) In the office, we started googling it, to see what it looked like inside and the next day, I brought in a pair of binoculars to have a better view. Lol. If I had read this, I could have bought a decent pair. :-)

Brilliant read. Nice to know that there are Underwater Binoculars too.

Dale Anderson (author) from The High Seas on September 13, 2012:

aethelthryth if you keep saying such sweet things you'll make me swoon and lose my balance, possibly fall overboard! And, so far, my record is unblemished in regards to involuntarily exiting my vessel. Well, one time I did walk off the end of the pier but that's another story...

Dale Anderson (author) from The High Seas on September 13, 2012:

I've always wanted to give airsoft a go, it looks like so much fun. Hard to play on a boat though.

aethelthryth from American Southwest on September 13, 2012:

I don't care about comparing binoculars, I only read this article to see if you could make a subject I am not interested in entertaining, and you did. I had no idea binoculars were that useful.

JP Carlos from Quezon CIty, Phlippines on September 12, 2012:

I sued to play a lot of airsoft and I buy differt optics. But as you pointed out, land lovers have different needs from seafarers.

Dale Anderson (author) from The High Seas on September 12, 2012:

Ahoy jpcmc! There's a lot of other things you could also consider but these are the main issues in my mind. Image stabilization is a hot topic for many but I don't think it's worth the money, personally. Thanks for reading.

JP Carlos from Quezon CIty, Phlippines on September 12, 2012:

This is really informative. I never thought that I have to consider a lot of things when buying binoculars. I'm a slave of marketing so I simply go for the brand. :) It's time to change the habits.

Dale Anderson (author) from The High Seas on September 12, 2012:

@Craig Hartranft: feedback taken, mate. I use pictures a lot because that's the way I remember things, visually. I make more doodles than notes when I'm writing something down that I know I'm going to need to remember so i cater to folk like me. It probably reveals a lack of literate education (left school at quite a young age). Regarding just talking about marine binoculars, it's what I know. Although many of the functions apply to other activities like hunting and bird watching, they are not within my real of direct experience so I'd be a bit of a fraud recommending 'nocks' for anything outside of boating. Thanks for taking the time to read and comment!

Craig Hartranft from Southeastern Pennsylvania on September 12, 2012:

Good information. But why speak to binoculars just for boating? It would have been more useful to speak about the basic characteristics and options of binoculars and then apply them to a variety of uses. And too many pictures ...

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