Reviewing The Best Marine Binoculars of 2021
Bushnell 7x50 Marine Waterproof Binoculars
Steiner Commander Marine Binoculars
Bushnell Fog Proof and Waterproof Binoculars
Ian Fortey Updated on May 27, 2021.by
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On land you may need a pair of binoculars just for fun. If you’re bird watching or hiking, they can be a real help. At sea, they’re much more. Marine binoculars can enhance your vision to improve safety on a boat. They can improve your field of view and allow for enhanced warning of danger. A good pair of marine binoculars can help you avoid other vessels, rocks, and more. They can also assist in finding landmarks, points of interest, and passengers overboard.
If you want to make sure you’re getting the best marine binoculars, we can help. Let’s take a look at the best binoculars on the market today.
Things to Remember
Marine binoculars are different than terrestrial binoculars. You could use any old binoculars at sea, but it may not be a good idea. At the very least, you’ll need high-quality hunting binoculars. Ones specifically designed to handle harsh conditions and bad weather. There are a handful of features you want to look for.
Maybe the most important feature of marine binoculars. After their ability to see at a distance, that is. Boats are unsteady, and that means you run the risk of dropping things. You need binoculars designed to handle bumps and drops.
A good pair of marine binoculars will have rubber armor on the outside. This can absorb shock and disperse impact across the frame. The frame itself should be polycarbonate or similar materials. Something able to withstand abuse.
You want lenses that have been coated to handle scrapes as well. One ill-placed scratch on a lens can really ruin your marine binoculars. Sometimes paying a little extra is what you need to do.
One of the big differences between regular binoculars and marine binoculars is grip. On the water, things get slippery. Normal binoculars could become slick in the spray of the sea. Good quality marine binoculars feature non-slip grips. The coating should be pliant but not sticky feeling. You want to be comfortable holding them.
The reason you need binoculars is to see at a distance. You want binoculars that offer good magnification. A good pair of 7 x 50 binoculars will often do the job, but there are others.
It’s good to be able to understand what the numbers mean when buying binoculars. In this case, 7 is the magnification. So you’ll have a 7x magnification on whatever you are looking at. The 50 refers to a objective lens diameter of 50 mm. The larger the objective lens diameter, the better you can see things. Larger objective lens diameters let in more light. But the trade off is weight. At some point, lenses get too big. So a 50mm objective lens diameter is often a good size for marine use.
When it comes to boating binoculars, 7×50 is an average. You can find other sizes that work well also. It depends on the other features and how you wish to use them.
Getting too high a magnification can be troublesome. It’s great to see further away. But it becomes harder to manage. Keeping things in view at a greater magnification is harder to do. This is why 7×50 is so common. For most boaters, it is the ideal mix to ensure clear viewing.
This refers to the distance between your eye and the lens itself. You need the right eye relief to have a clear image. The eyecups on your binoculars manage this for you. Some binoculars have adjustable eye cups so you can still view with glasses on. If the eyecups are not adjustable, it can be hard to use binoculars with glasses.
Typically there are three kinds of focus. Center focus binoculars have a dial in the middle. As you spin the dial one way or the other, it focuses both lenses simultaneously. These are very common and easy to use. You can usually use these easily even with glasses on. One of the big upsides to center focus is range. You can focus easily on things even close up.
Another kind of focus is individual focus. This allows you to focus each lens separately. Doing this allows you to have greater clarity. It can be harder to focus on things that are close up, however.
Lastly, you may find autofocus binoculars on the market. As the name suggests, these try to automatically focus on the object ahead of you. They can be frustrating, however. Many phone cameras use autofocus. No doubt you have experienced it trying to focus on the wrong thing. That is a problem with binoculars as well. If there is more than one object in view it may focus on the wrong one.
Field of View
Field of view refers to how much you can see in the distance. The greater the field of view, the easier it is to find what you’re looking for. If it’s too narrow, you may easily lose your target. Typically this is measured at 1000 yards. Your field of view is how many feet you can see across the horizon at 1000 yards.
Sometimes field of view is explained in degrees. Every degree in a field of view represents 52.5 feet. You may find binoculars that offer you 6 degrees of view, which would be 315 feet.
As magnification increases, field of view decreases. Most boating binoculars will offer a field of view between 300 feet and 350 feet.
For people not into the technical aspects, optics can be confusing. The words “porro prism” and “Bak 4” don’t mean a lot.
Bak 4 is something called Barium Crown Glass. It is high quality glass that makes high quality prisms. It transmits light very well with little being lost.
Bak7 is a similar product but it is less dense. It is cheaper and doesn’t do the job as well. Bak 4 is the superior choice if you want high quality images.
Porro prism is a kind of prism used in many binoculars. It’s named for its inventor, Ignazio Porro. Light enters through the front lens of the binoculars. It hits a prism at the back of the tube. That prism directs the light in a zig zag pattern to another prism. That prism then sends it to the ocular lens where your eye is located. This can offer very clear, 3D images. They also provide a greater field of view of depth perception.
You can tell if binoculars use porro prisms just by looking at them. If the lens where you put your eye is not directly in line with the lenses at the end, it’s a porro prism. If all the lenses line up, then that’s a roof prism.
Roof prism binoculars are H-shaped. Everything lines up straight. These binoculars tend to weigh much less than porro prism ones. They can be smaller and easier to carry around.
The prisms inside of a roof prism pair overlap. Though they are lighter and smaller, they are also more expensive.
Waterproofing and Fog Proofing
This is one of the big points for marine binoculars. Normal binoculars often are not fog proof and waterproof. But if moisture builds up in binoculars, they can be rendered useless. The moisture condenses on the lenses inside and you can no longer see. This is a constant hazard on the water.
Good quality binoculars are sealed with o-rings. The inner tubes are then filled with gas. This is often dry-nitrogen but sometimes argon is used. The gas changes the atmospheric pressure in the tubes. Because the tubes are under pressure, it prevents moisture from entering. Nitrogen cannot hold moisture, so these binoculars stay dry internally.
The outside lenses can obviously still fog up and get wet. Fortunately, it should be easy enough to wipe them clean.
In terms of waterproofing, you may need to read carefully. No binoculars are going to be fully waterproof. Like watches and cameras, at a certain depth the pressure will become too much. Hopefully, you never drop your binoculars fully in the water so they can sink. But if it happens, they may fail at a certain depth.
On the water, you always risk losing something overboard. That’s why we have PFDs for passengers and crew. But your binoculars may need something as well.
Not all marine binoculars can float. In fact, many do not. The materials needed to make them are generally not buoyant. There are some models that will float on their own. However, many rely on buoyant straps. Foam wrist or neck straps that act as a PFD for your binoculars. If you don’t have binoculars that float on their own, make sure you get a strap that does.
There are many extra features that modern marine binoculars can offer. One of the most common is a compass. Simple models may just have a small compass on top you can read. Others will have an electronic compass. The read out is displayed over your field of view inside the lens.
Imagine stabilization is another feature of some binoculars. At the maximum distance, viewing can be tricky. Minor shakes in your hand can cause the image to rock right out of view. Stabilization helps even out these minor movements. That improves image clarity. Also, your ability to hold an image in focus.
Rangefinders are another feature that some binoculars may offer. An infrared system is used to measure the distance between you and an object like another boat. It will display on the rangefinder reticule inside the binoculars.
Some models include what is known as an inclinometer. While a rangefinder shows the distance, an inclinometer shows angle of incline. That means the elevation of something, or how high up it is compared to you.
As with most things in life, you need to be aware of the price of binoculars. Buy the best you can afford at the time is always a good piece of advice. Marine binoculars can greatly range in price. Some may be around $100. Others can cost over $1000.
Only you know for sure what you need from a pair of marine binoculars. If it’s just something you want for fun, maybe you don’t need to invest a ton. But if you’re a serious boater and work on the water, you’ll want a reliable pair. Higher quality binoculars often cost more.
More expensive doesn’t always mean better. Check the features and find the ones that give you everything you need. There are many options that are still affordable and do a good job.