No sailing or cruising boat is complete without a pair of marine binoculars. even if you have the most powerful eyes. how far can they see not to talk of seeing details from afar. That is when a pair of quality boating binoculars comes very handy.
When it comes to selecting binoculars to use on a boat, you have to take into consideration the type of conditions the sea or river waters introduce into your ride. It’s not the same as when you are on land. Knowing the conditions you will be using your pair of binoculars under will determine which type of binos will be ideal for you.
when it comes to how to choose binoculars for sailing, boating, marine or yachting, it can be confusing if you are not very familiar with what to look for, it can become a tedious process. But it should not be so. Knowing which magnification power to look out for or prisms; if coated optics are important or not is not always easy.
Just like my recent article on how to select hunting binoculars, the first considerations you have to look at are:
How much are you willing to spend on your binoculars?. This will help you narrow your search down to the range you want. there are many binoculars in the market that provide different quality of images and how long you can see. Here are the sizes you can find.
- Compact with lenses between 25mm – 28mm in diameter,
- Mid-sized with lenses at around 30mm in diameter,
- Full-sized with lenses in the 40mm – 42mm range,
- Larger sized with lenses 50mm in diameter and above.
the second thing to consider is:
- Your needs
are you looking for something lightweight and not too sophisticated. If you need it for shorter distance viewing, then you will need a pair that is compact and you can easily hold with your hands and get a quality image while moving in the boat.
But if you are in need of a long-range pair, you will need binos which are image stabilized for long-distance viewing.
Features to Look for When Choosing Marine Binoculars for Sailing or Boating.
With sailing introducing specific data into your environment, those data will determine which features are most important than others. The weather conditions, the movement of your body while in the boat will all affect the type of binoculars you use.
- Magnification Power
- Field of View
- Eye Relief
- Lens Coating
- Weatherproof construction
- prism type
- image stabilized
Now let us go into more details and what to expect from each of these features that will enable you to select the right binoculars for your marine activities.
In every binocular, you will find numbers like this “7×50” in millimeters. This number indicates the magnification power of that pair of binoculars. The first number(7×) is called the magnification power also known as binocular power. Magnification power of 7 means that an object will appear 7 times closer than it would to your unassisted eye. Beware that high magnification above 10× amplifies your hand’s movements thereby producing unsteady images.
The second number is the objective lens diameter size which is 50mm. The diameter of the objective lenses largely determines how much light your binoculars can gather from the object you are viewing and hence how further you can see. the higher the objective lens size, the heavier or bulkier your binoculars will be. As a high objective lens size means a bigger lens.
So the optimal magnification power for sailing binoculars is 7×50mm. This is the classic magnification power for marine use.
Field of View
Most 7×50 marine binoculars have a field of view in this range 6º to 8.3º, The field of view which is often denoted as (FOV) describes the width of the image you see, measured in feet at the distance of 1000 yards.
The narrow this number the more difficult it will be to get more details when viewing because it might affect your eye relief. The wider the view, the easier tracking is, but that may come at the expense of image sharpness, especially on the edges.
This is the optimal distance from the eyepiece to your eye for viewing. If you are a glass wearer, it is important to consider this although many binoculars offer diopter adjustments to allow for glass-free viewing.
If you insist on having your glasses on, then you will need some that have collapsible eyecups to accommodate your eyeglasses. Generally, it is good to choose larger eye relief if you are going to be using your binos for longer hours to avoid putting strains on your eyes.
Lenses are often coated using one or more thin layers of chemicals (most commonly magnesium fluoride) reducing internal reflection from around 5% to 1% or less. Internal reflections reduce the brightness, sharpness, and contrast of the image.
You will often identify quality lens coatings with the look of the lens surface. The quality ones appear as subtle tints of blue, violet and green.
Also, better binoculars include more layers, with more complex chemical combinations, on more surfaces, to achieve their amazing light transmission efficiency.
Here are the coating types:
- Coated: one or more surfaces coated with a single layer.
- Fully coated: all air-to-glass surfaces are coated with a single layer.
- Multi-coated: one or more surfaces coated with multiple layers.
- Fully multi-coated: all air-to-glass surfaces are coated with multiple layers.
The more coating layers of the optics, the better your images will be when viewing.
Weatherproof here mean water and fog proof binoculars. The environment you will be using these binoculars in is the water area. Although not a deal-breaker, it will be wiser to get a pair that is fully weatherproof so that in case it falls into the water. The damp marine environment, combined with changes in temperature, causes interior lenses of non–waterproof binoculars to fog.
The popular prisms used in binoculars are the roof prism( they look like a straight tube which is easier to hold) and the other is Porro prism named after the inventor Ignazio Porro( binoculars with a dog-leg shape)
There is a debate around which one is the best. Even though Roof prism binoculars look more appealing and simple but they are more complex to manufacture as they require more precision to make. This made roof prism binoculars cost more but manufacturers kept on perfecting it and eventually succeeded because they were appealing more.
Today, roof prism dominates the market. But dollar for dollar Porro prism still delivers better optical performance. That is because Porro prism design is simpler and more light efficient, and its images showed better contrast.
Because their objective lenses are farther apart. However, some roof prisms with phase shift coating provide excellent performance.
The prism glass comes in two types; BK-7 and BAK-4. BK-7 uses boro-silicate glass and BAK-4 use a denser, finer barium crown glass, which eliminates internal light scattering and produces sharper images than BK-7.
The higher the quality of the glass used in the binos, the higher the price will be. Roof prisms are lighter and compact, but they are more difficult and complex to make. so they are more expensive than Porro prisms.
In years passed, image-stabilized binoculars were only found mostly with the forces. Today, there are image stabilized binoculars for civilians to also enjoy. There are some manufacturers making them and you can find them in the market and purchase.
These type f binoculars use a technology called image stabilization technology(IS) to stabilize the image you are viewing by manipulating the lenses to continuously compensate for movement of the binoculars in your hands.
Hence allowing boaters and sailors to achieve a steady view at higher magnifications that enable you to see far past the traditional 7x marine binocular.
With image-stabilized binoculars, you can even use the 10x, 12x,15x, or even as high as 20x magnification binoculars and yet still achieve steady images and the allow you to see far clear images.
Do you need a built-in compass or rangefinder reticule?
Will you desire to find the bearing of objects from the sea?. The built-in compasses which usually appear superimposed near the image you see through the lens, help you identify the bearing of the object. They are recommended for marine use.
Rangefinder reticle in the binoculars enables you to calculate the distance of the object from your standing point. If you know what the height of the object is (often printed on charts) and can measure the angle to its top. then using binoculars which has rangefinder reticle can calculate the distance for you.
Individual focus, center focus or fixed focus?
This is a matter of preference. Most marine binoculars are of the individual focus variety; meaning the user focuses each eyepiece separately, negating the need to focus every time you use the binoculars.
In center-focus binoculars, one eyepiece adjusts to accommodate the difference between your eyes. A central focus knob then adjusts both sides simultaneously for distance. The center-focus is often preferred by those sharing their binos with others and is easier to use for most people.
With Auto-Focus, once you’ve adjusted your ocular settings for differences in your individual eyes, you won’t need to adjust the binocular again for varying distances. It works best when you have to grab your device quickly so that you don’t miss an action. Its a set- and -forget system.
Many marine binoculars these days come with it but you can also purchase it separately. They help you secure your binoculars around your neck in case you don’t want to be holding them all the time. Maybe you want to swim, if they are waterproof you can swim with them. They are there to also avoid losing them.
In the end, your budget and needs will dictate which features your binoculars will have. Like I said earlier, the “7×50” magnification power is popular among mariners, boaters, and sailors because of their ability to deliver optimal images even with the moving of the hands.
If you wish to have higher magnification, then choosing image stabilized binoculars will be your best bet but they are in the mid and high price range. Meaning you are willing to invest more for long-range and better quality. having them waterproof is also good as you know the marine environment is generally damp. The choice eventually is yours.
When it comes to how to choose binoculars for Sailing, Boating or Marine, it’s not always easy as there is an overload of information on the web. But if you read this article carefully, know what you want, it will make it easier for you to select the best for yourself.
It’s your turn!! Lest hear from you!.