How to Choose Good Binoculars for Sailing and Yachting

When looking for the best pair of binoculars for you to use on a boat, the sky is your limit. It is actually easier to look for one if you are on a rush. But if you have a very ample time to look for one, you will realize that it is not an easy task for you to do.

To help you look for the best pair of binoculars for your next boating trip, here are some tips for you to consider.

Binocular specifications

Binocular specification is composed of two numbers. The first number describes how can the binocular magnify a certain image, or its power. The second number, at the other hand, describes the diameter of the objective lens in millimeters. Just so you know, the objective lens are the lenses found at the from of the binoculars.

In the purpose of understanding these numbers more, lets take an example. Suppose we have 7 x 50 binoculars. This binocular can magnify an image up to seven times its original size. As you increase the magnification of the image, the brightness also decreases. This means that a pair of binoculars also need larger objective lenses to maintain the level of brightness even magnification increases. Larger objective lenses can gather more light than those smaller ones.

What to look for in a marine binocular?


Binoculars designed for birdwatching and other inland activities has a very high magnification level. This makes them inappropriate for use in water activities. The higher magnification level is applied to an image, the more difficult it is to keep an image stabilized. That is why a 7x power is the suggested magnification level for small boats. However, if you really need a pair of binoculars which has more than 7x power, then you can opt to buy a pair of binoculars which has an image stabilizing feature for you to have a more comfortable viewing experience with a magnification level of up to 18x, as they can adjust to the movement of the surroundings.

Waterproof design

You are of course surrounded by water when you are aboard a boat. Added with moist air and unstable temperature in your surroundings, your binoculars will surely form a fog in its internal lenses, especially if they are not built for boating use. Therefore, you will surely need binoculars with a waterproof design, preferably the ones with an o-ring sealed interior and filled with dry nitrogen. It is also suggested to have a binocular with a flotation device just in case your binoculars fall into the water.

Image stabilizing feature

Binoculars with an image stabilizing feature can give you a steady image, making it perfect for bouncy boats. You cannot get a steady image while you are aboard a boat because of that bouncing and rolling action of the water while the boat is afloat. This is why you really need to have a binocular with that feature. Image stabilizing binoculars automatically adjust to all those unnecessary movement while giving you a very detailed image even you are magnifying up to 18x power.

Aside from these features, you may also choose if you get a pair of binoculars with either a built in compass or rangefinder reticule. Here’s the difference between the two.

  • Built in compasses can be usually seen as an embedded feature near the image when you look through the lenses. It allows you to take bearing from an object that you can’t see when you use a non-magnified handheld compass. It is strongly suggested for use for water activities.
  • Rangefinder reticules aides you in measuring the distance from a certain object if you know its height and the angle to its top.

Types of Focus

Binoculars do have many types of focuses in order for it to compensate differences between eyes and different distances. Center-focus binoculars has a single eyepiece that can accommodate the difference between your eyes. To adjust both sides at the same time, a central focus knob is used.

Sport auto focus on the other hand is a fixed focus system that has a very deep field depth and can be found on steiner binoculars. Sports auto focus allows you to see varying distances quickly without readjusting. It works by just doing a one-time ocular adjustment for differences in your individual eyes. This way, you can’t miss any action as you can just grab your binoculars and see it.

Types of lens coatings

Around 5% of light is reflected back every time light enters or leaves a piece of glass. There can be as many as 16 air and glass combo surfaces embedded in your binoculars. There can be a lot of internal light bouncing around inside, thus decreasing the brightness, contrast and clarity of the image. To reduce internal reflection, the lenses are coated with a single or a mixture of chemicals. One common chemical used to coat is magnesium fluoride. That is the reason why these lenses look like they have shades of blue, green or violet.

The types of lens coating include: (1) Coated, in which one or more surfaces are coated with just a single layer, (2) Fully coated, where all air and glass surfaces are coated with a single layer, (3) Multi coated, like coated but with multiple layers, and (4) Fully multi coated, like fully coated but with multiple layers.

Types of prisms

Prisms are used to invert and magnify an inverted image. There are two types. One is the BK-7 and BAK-4. BAK-7 makes use of boro-silicate glass while the BAK-4 uses a denser and finer barium crown glass that reduces internal light scattering and can produce more detailed images than the BK-7.

For your maximum enjoyment when watching birds and other sceneries from your boat, it is important to have the best binoculars designed for use in water. With these information, you can now choose the best binoculars for your next marine trip.