If you go out on the water on any kind of vessel, be it a sailboat, dinghy, motor boat or anything else, you will most likely need decent marine binoculars. They are one of the primary things in a navigator’s kit.
The reason you will need binoculars is that many important things will be very hard to see with the unaided eye. These include landmarks, buoys, other boats and even debris or rocks sticking out of the water. The reality is that out on the water, things of interest are usually quite far away, with a vast expanse of water in between. In this sense, being on the water is different from most land-based experiences, where the landscape and objects obscure the more distant stuff.
I’ll suggest one particular product that will fulfill this purpose perfectly. After that we’ll go into a lot more detail on choosing the best marine binoculars for your particular situation and budget.
A lot of times, you may find yourself out on the water at dusk or dawn, or even after dark, and you need to see your surroundings in low light. The Steiner bino is one of the best marine binoculars to take with you onto a boat or ship because of its superb light transmission capabilities. The result is that typically the image you’ll see through the eyepiece will be brighter than what you’d see with the unaided eye. Definitely one of the best products you can get for the money.
In general, Steiner is one of the top brands in the marine binocular and military optics industry. If you think about it, these two situations set the bar for optical tools very high: they need to perform superbly in terms of optics, but they also need to be robust and be able to withstand very rough handling – something that optical instruments are rarely good at.
What you’ll find is that the Steiner Marine binocular is a very sturdy and well-built device. It has a protective rubber coating and is waterproof. Remember that on a boat, it’s not uncommon to accidentally whack the binos against something when pitching and rolling on the waves. The rubber coating also helps in preventing the binoculars from sliding when set on a table or deck. It’s also perfectly normal to get spray on your optics or even send them into the drink. Being waterproof is crucial. Note that these are not “floating” binoculars, but this can be solved using a special floating strap from Steiner.
As is common with marine-oriented binoculars, the Steiner Marine have an autofocus feature. This doesn’t mean they autofocus the same way a digital camera does. Instead the optics make use of your eyes’ innate focusing ability – anything further than 20 feet (about 6 meters) will instantly go into focus as soon as you look at it. You’ll only have to adjust the individual focus for your eyes once. The downsides have to do with sharing – another person will first have to adjust the focus for their eyes; and with lack of close focus – you can’t look at little things close-up with these binos.
Having been developed specifically for use on the water, this bino is one of the best deals you can get for their price. If you go over to Amazon and read some reviews, you’ll find that most people have been hugely satisfied with their purchase.
After this one recommendation, it’s time to go over the basics involved in choosing binoculars for marine use and then have a look at some other excellent choices that are available on the market.
Probably the main reason you’re buying binoculars: to magnify stuff. This number is possibly the easiest to understand of all when it comes to optical instruments: it’s how much larger do they make things look. An 8x magnification means the viewed object will look 8 times bigger than without aid. You can also interpret this as saying that the object will look as if it’s 8 times closer to you than in reality. This is due to the way perspective works. So a ship some 1000 yards away will look as if it’s only 125 yards away, if you use 8x magnification.
You’ll notice that binoculars are almost always described using two number with a letter ‘x’ in between. The first number would be the magnification.
When choosing binos specifically for boating and such, the recommended value is 7x. You’ll also be quite fine with 8x, since the difference is so minimal. However, keeping 10x or more steady and getting a stable image while the boat is rocking back and forth will be challenging, so higher magnification values are not recommended. You’ll also lose a lot of field of view when you go higher on magnification which will reduce your ability to take in a larger scene and to judge distance, speed and size of distant objects.
Objective Lens Size
The size of the lenses at the front of your binoculars – called the objective lenses – matters quite a lot. This is the place of entry for the incoming light and the wider the entrance, the more light comes in.
The bigger your objective lenses, the brighter images you can expect. Don’t underestimate the importance of this when going into the sea. Twilight conditions and bad weather mean low light – and that’s when not noticing other vessels or obstacles can be particularly dangerous. You want your binoculars to help you spot danger before it becomes a problem.
Typically, marine binoculars are made with 50mm lenses (that’s the second number, the one after the letter ‘x’ in the description). You can get away with less, such as 42mm, as long as the optical quality of the product is really good. But 50mm are really the classical skipper’s binoculars.
This number will be important when considering how well the instrument will perform in lower light. If you divide the lens diameter by the magnification factor, you’ll get the exit pupil. You can think of it as the size of the beam that enters your eye – the wider the beam, the brighter the image.
A classical 7×50 model will have an exit pupil of more than 7mm, which is superb. Otherwise, go for at least 5mm.
If you use binoculars while wearing glasses, you’ll need to make sure that the binos have enough eye relief. This is how far you can hold the eyepieces away from your eyes and still have a full field of view. Since eyeglasses “protrude” forward, you should make sure that you have eye relief of at least 15mm, though 17mm or more would be better. It will certainly depend on the shape of your glasses and your face.
To make binoculars usable for both people who use spectacles as well as those who don’t, manufacturers typically make adjustable eyecups. If you need the extra space for eyeglasses, you can push them in, and if not, you can pull them out for more comfort and to block surrounding light.
The eyecups may be simple rubber ones that can be rolled up or down. The downside of these is that they’re not very convenient and the rubber may start failing at some point. The other option is twist-up eyecups which change positions with a quick firm click. These are easy to use, but don’t block the light from the sides as some specially shaped rubber ones.
Prism Type: Roof or Porro
Little angular bits of glass inside the binocular, called prisms, turn the image upright. Without them, you’d see everything upside down, or inverted. Since binoculars are mostly used for observing “earthly” things, this is crucial. Many astronomical telescopes, on the other hand, don’t have prisms and produce an upside-down image, since “up” or “down” don’t make as much sense when looking at celestial objects.
There are two types of prisms in use nowadays:
You can identify Porro binos by their shape: the front lenses are separated and the barrels are not straight, but kind of stepped. Classically, marine binoculars have been of this type. One reason is that Porro prisms tend to have better light transmission. Plus, it’s easier to make binoculars with big objective lenses and better depth of field (“3D vision”) when using Porros.
On the downside, Porro configurations may be quite heavy and not very ergonomic – they’re just not as easy to hold, especially single-handed.
Roof prisms allow for much more compact construction, resulting in more-or-less straight barrels. Such binos are smaller, lighter and generally more ergonomic than their Porro prism counterparts. Most “general use” binoculars nowadays have roof prisms, and they’re popular with birders, hunters, hikers etc.
Traditionally, it has been assumed that Porro prisms offer an advantage in light transmission over roof prisms, in particular because of fewer times light has to be reflected or cross air-to-glass boundaries. Recently however, optics have witnessed huge technological progress and a lot of that advantage has been reduced.
That, plus the convenience of use, are the main reasons why roof prisms are becoming more popular amongst boaters, yachtsmen and sailors. It’s definitely worth considering a good mid-range roof prism binocular even if you’re planning to use it on the water. It’s also more convenient to use when they have to change hands often due to simpler center-knob focusing.
Glass Quality and Lens Coatings
It’s common sense that the quality and make of the glass components inside an optical instrument will have major effect on the quality of the images produced. Some things to pay attention to, are:
BaK-4 prisms: This is a high quality glass that reduces the amount of light lost during internal reflections. Just so you know, BaK-4 is better than BK-7.
ED glass or extra-low dispersion glass reduces the amount of “chromatic aberration”. This is when the edges of objects viewed through the optics have a “rainbow” fringe – usually a thing you don’t want to have. ED glass typically raises the price of binoculars significantly, but you can still get good mid-range binos with ED glass.
Fully multi-coated lenses – whenever light passes through a lens, some of it will be reflected back. This loss of light results in dimmer images. There have been major technological advances in lens coatings – special layers on the lenses that reduce the amount of light lost in this manner. A binocular can have a dozen or more air-to-glass surfaces on the inside, each of which contributes to light loss. For this reason, you want to look for a model which offer fully multi-coated lenses, meaning that all such surface are coated, and not once, but several times for the best possible light transmission.
Waterproofing and Build
As we all know, spray from the waves and bad weather can make things wet on board a sea-faring vessel. Ocean air is also very moist even when the weather is nice. Water and moisture can (and will) get into a poorly made marine binocular, fogging up lenses and possibly rendering the whole thing unusable.
Getting a waterproof and fog proof product is imperative for this kind of use. Also, pay attention to “nitrogen purged” or “argon purged” products: this means that the inside is filled with an inert gas that will prevent seams from corroding due to the moisture and salt in the air, making your product last longer.
Optics are gentle things and boats are really not the best environment for them. You want a marine binocular with a nice sturdy construction, so it can take a few bumps during wavy moments. Since you don’t want the bino slipping from your hands or sliding around when set on deck, a rubber coating is always a plus.
Top Picks for Marine Binoculars
That’s a lot of information, I know. If you haven’t processed everything above or haven’t even read it, it’s okay. We’ll now take a look at some of the best marine binoculars to buy. None of them should leave you disappointed even if you don’t understand all the specifics.
I’ll start by listing this amazing product, knowing well that this is not one for everyone’s wallet. Steiner is one the top makers of marine binoculars and the Commander series, I believe, is their high-end answer to the demand.
It looks a lot like the first product I recommended at the beginning of the article, but really, it’s in a league of its own. It’s not even worth mentioning that the optical quality is exceptional, this is a given. In lower light, you can expect to see images that are actually brighter than what you’d see with the unaided eye.
There’s a whole number of features that make this the dream bino for a mariner. First the stabilized internal compass. Since you see the compass readings while looking through the glass, it’s much easier to use it while trying to navigate by chart or when indicating the location of some object to another person.
Then there’s the range finding reticle. If you know the size of a distant object, a quick calculation will give you the distance to it. Don’t confuse this with laser rangefinders – those are a completely separate class of tools.
The build: as the cliché goes, they’re built like a tank. The lenses are mounted on flexible supports to dampen shock, and thanks to the protective casing, the bino can withstand a significant impact.
As with many marine binoculars, you get an “auto-focus” system: set the focus once and then enjoy instant focus on any object beyond 20 feet – very convenient when out on the water.
The reality is that this here is a serious tool for people whose life is tightly connected with water, either professionally or due to lifestyle. If you’re a captain, skipper, bluewater sailor, long-term cruiser etc, this is certainly a product to consider and it should be taken as an investment into your job or lifestyle.
The Steiner above may have made your head spin, but it’s perfectly understandable if it’s way beyond your spending limit. Have a look at this Bushnell product for a much cheaper alternative. Obviously, don’t expect it to be in the same league as far as the optics or build quality goes, but it will get the job done.
This one is also a 7×50 configuration and has an internal compass. The field of view is quite nice at 350 feet at 1000 yards and it has multicoated lenses and BaK-4 prisms. So you get pretty good optics for a very affordable price.
A nice feature of this Bushnell is that it actually floats in water by itself. Now, I don’t think you’ll be dropping your precious optics in the water all the time, but it’s nice to know that you at least have a chance of retrieving them should that happen.
The constuction is quite sturdy and they’re of course water- and fogproof, so they’ll survive most boat trips. I think this model is a great bargain if you go out on the water casually or need optics for things like open water fishing, whale watching etc.
Usually, it would be unthinkable to use a 15x binocular out on the sea: the motion of the waves would make near unusable. But not in this case.
The special thing about these high powered binoculars is their built-in image stabilizer. Canon is well known for their photographic lenses and they use their tech for making image stabilized lenses in these binoculars. In fact, the 15×50 is not the only IS option from Canon – there are many other configurations.
The way the image stabilization works is by automatically tilting a little lens inside the barrels to compensate for any shaking or vibrations coming from your hands or the outside environment. For this reason, it’s possible to use them without any support even at these high magnification factors.
They’re not cheap, and you do lose significant field of view due to the magnification, but imagine looking at a vessel, wildlife or landscape element from your boat and seeing it 15x larger. It’s a great tool to have with you. You may consider having a pair of “normal” binos with you as well though.
I think it would be unfair to only name Canon when it comes to image stabilization binoculars. This technology is a big deal because it allows to experience much higher magnification and detail in situations where it would otherwise be impossible.
Another big name in this area is Fujinon. Their IS binos are well-known and highly praised, including this 14×40 model. Again, 14x is a huge factor when it comes to any handheld optical device – a good reason to check them out.
Finally, I wanted to recommend a product that most people wouldn’t consider to be a marine binocular. As I said above, roof prism binoculars are becoming increasingly popular with the seafaring crowd, in particular for their convenience and ergonomics.
If you go for roof prism types, I suggest looking at 8×42 configurations. 8x is about as high as you should go and 42mm objectives provide sufficient light for effective use on the water. One of the best products currently on the market is the Midas by Athlon Optics. Don’t let the little-known brand discourage you – just read the user reviews over at Amazon to know that this is a great buy.
The Midas offers superb light transmission due to high quality optics, almost on par with $1000+ high-end European brands and their field of view beats almost every other bino on the market. If you’re a casual boater, or you need an extra pair of binos to supplement your main set, then this is an excellent choice to go for. They will be a great companion not only on the water, but everywhere else as well.
As you can see, the marine environment puts certain constraints on the type and configuration of binoculars you can go for, but thankfully there’s plenty of choice nonetheless. It’s best to figure out your budget first (and be ready for a substantial outlay if you want quality) and then pick the best marine binocular in that range, using the buying guide and product reviews above.
- Brands that Make Great Optics for Use on Boats, Ships etcIn this post, we look at some of the best optics brands that produce marine binoculars for yachting, sailing etc.
- Why Binoculars are Essential If You're Going Out to SeaBinoculars are an inseparable part of boating. Here we look at the different reasons you might need binoculars while in your boat out on the sea.
- Extra Features Found on Marine BinocularsA good look at all the extra features often added to marine binoculars that greatly increase their usability and also their price.
- How to Choose Good Binoculars for Sailing and YachtingWe look in detail at all the aspects of choosing great binoculars for boating, sailing and yachting.
- Why 7x50 is the Most Common Bino Size for Use at SeaYou've probably heard that 7x50 are possibly the most commonly encountered marine binoculars. Here we examine why that is the case and whether you should go for this size.
- Best Binoculars for Boating in 2018 - Reviews and Buying GuideRead our in-depth guide and detailed reviews of the best marine binoculars for boating. We cover everything you need to know about choosing the best product and review some of the best options available on the market.