Why 7×50 is the Most Common Bino Size for Use at Sea

Binoculars aren’t just made to make your birdwatching a much enjoyable experience or for you to have a better view at concerts and other events when you only have the cheapest ticket. Binoculars however is a very high tech piece of equipment that makes everyone’s outdoor experience a whole lot more fun. Hunters trying to hunt animals are usually the ones who uses a pair of binoculars at a more regular basis, however they are also important for people who likes to wade on the wide seas for their enjoyment. Truth be told, a nifty pair of marine binoculars are a very useful piece of equipment for seamen and seafarers.

People who likes to spend their idle times on the water must feel the need of having a good pair of marine binoculars. Aside from using it as an accessory, marine binoculars aide navigation and safety big time while on the water. They also aide you in spotting some important navigational tools in the water like buoys and day marks. They also help you spot other vehicles in the water like boats, ships and yachts, and some foreign objects like landmarks, light houses and storms to protect you from any harm or danger while on the water. As it can help you spot any danger in advance, then it can also give you an extra time to prepare and avoid dangers that may come to them. Therefore, marine binoculars aren’t just a toy or an accessory while on the water but it keeps you safe and protected from any danger.

It is known to the world of seafaring and other aquatic activities that the regular size for marine binoculars is 7×50. The numbers mean it has a magnification power of 7x and its objective lenses measures 50mm in diameter. While some might say that the 7×50 specification of binoculars are the most common in the marine industry, some may also disagree with it. So, to clear it up, why 7×50 is the most common size for boating binoculars?

First, let’s explain what these numbers really mean. This combo of numbers tells us the degree of magnification and the diameter of the objective lenses, usually measured in millimeters. In this case, a 7×50 pair of marine binoculars tells us that the target object or the image you see in the lenses can be magnifies by up to seven times its original size based on the first number. Having a large magnification rate however does not guarantee you of a great image. For instance, a higher magnification level decreases your field of view does seeing tiny objects at sea more difficult.

The second number tells you the size or the diameter of its objective lens which is usually measured in millimeters. In this case, a 7×50 pair of marine binoculars has a diameter of 50 millimeters. One thing you should remember about the size of the objective lenses is that the larger your lens is, the more light it can collect. This is a factor you should not be missing out since it could be very important especially when using your binoculars on low-light conditions or during nighttime. Having two times the size of a usual objective lens size makes your binoculars gather light four times its usual capability.

This explanation makes everyone on the marine or boating industry choose 7×50 marine binoculars the best one to choose for their aquatic activities. However, you should also check out its other features. There is what they call the exit pupil wherein it describes the diameter of the beam of light that leaves the eyepiece and is measured by millimeters. Having a much larger beam generates a much luminous image making it very useful at night time or in low light conditions. By theory, the exit pupil must be more or less equal to the diameter of the pupil of your eyes after it adapts to the darkness. The size of the pupil of your eyes when in darkness typically decreases as you get older, but usually, it measures between 5 to 7 and a half millimeters. To compute the exit pupil in millimeters, you should divide the size of your marine binocular’s objective lenses by the magnification degree. Getting a pair of marine binoculars that has a very high magnification levels is strongly discouraged especially if you regularly engage in boating during lowlight conditions like fishing early in the morning before the sun rises.

Now that you know what these numbers of the marine binoculars mean, now you should know why 7×5 marine binoculars are the most common size for a marine binocular. There are actually three reasons why 7×50 marine binoculars are the most sought kinds: conventional magnification level, large objective lens size, and substantial exit pupil size.

It has been common for everyone to buy something that comes with its largest size, and marine binoculars are not exempted wit that. Mariners usually start looking for something that has a very large magnification levels. However, as you increase your magnification, you also tend to increase instability and shaking of the image because your hands are also shaking. Image instability is a very inevitable event to happen even if you got the steadiest hands. Add the unstable and the rocking motion while on the water and an even unsteady image will form at your binoculars. That is why you need to keep your magnification levels somewhere at seven to have a somehow steady image.

A 50mm objective lenses is just a right size to collect more light, thus allows you to view even in the most extreme dark conditions that makes sea farers problematic on a regular basis.

But maybe the most advantage a 7×50 binocular has is its large exit pupil or the size of the image formed at the eyepiece. A large exit pupil allows you to view an image even if your eyes and the binoculars aren’t accurately aligned due to the motion of the surroundings.

To sum it up, a 7×50 binocular has a set of lenses and magnification levels which are in coordination with each other. So, try to look for a 7×50 binocular the next time you shop for a new pair of marine binoculars.