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What Does 10×50 Mean For Binoculars? [Are These Right For You?]

When looking at binoculars, you will soon notice two numbers separated by an ‘x’. But what do these two numbers refer to and what do they mean? From there, what impact does this have on how and when they can be used? I spent some time researching to find out for good. I’ll be sharing this information here with you today.

So, what does 10×50 mean for binoculars? The first number on binoculars refers to the magnification power, whereas the second refers to the size of the objective lens, in millimeters. For 10×50 binoculars this means that using them will display an object 10 times larger than that of the human eye. An objective lens is responsible for gathering light, with 50mm enabling the user to benefit from up to 8 times more light and improving their seeing conditions.

You’ll routinely see binoculars marketed via the size of the magnification power and the size of their objective lens.

Whether this is 10×50, 15×70, 20×80, and so on and so forth.

Each will have been designed and intended for different uses. It depends entirely on what a user wants to see, under what conditions, and of course how far said object is away.

Let us now take a closer look at these numbers in further detail, before we look at some of the situations and circumstances where 10×50’s would be ideal to use.

So, be sure to keep on reading if you are in the market for a pair of binoculars and want to ensure you get the right pair, for you.

The Numbers On Binoculars

There are multiple different numbers to consider on binoculars, although the two most commonly sought after are the magnification and the size of the objective lens.

The magnification capabilities are almost always displayed first.

It will always be expressed in relation to the size that an object would be seen with the naked eye.

So, a 10×50 pair of binoculars would have 10x magnification, a pair of 20×80 binoculars would have 20x magnification.

You should also consider that magnification is about keeping the object close to your eyes when you observe through the binoculars.

Equally, you will also find binoculars on the market that have a variable zooming ability. These will commonly be marketed as a range, e.g. 10-30×50.

This simply means that magnification can be controlled and changed based on the user’s preference, 10x magnification at a minimum, and 30x at a maximum in the context of our example.

The size of the objective lens is the other commonly used number, and that will typically make up the title of the product.

Measured in millimeters (mm), this is the size of the lens positioned at the far end of a pair of binoculars.

These control the amount of light that is taken in; which impacts what can be seen and when.

Generally, the larger the objective lens, the better the binoculars will be in lower light conditions.

This is why many binoculars used for astronomy, or other dark hobbies and pursuits, often have objective lenses on the higher end.

Consider, however, that the larger the objective lens, the bigger and heavier the binoculars will be and will consequently be less versatile.

The other two numbers to be familiar with on binoculars is the exit pupil and the eye relief.

The exit pupil determines the amount of light that come through the eyepieces towards your eye. Generally, the large the size of the exit pupil the brighter the object will be shown.

The eye relief is the amount of space a user can have from the eyepiece, while still being about to obtain the full field of view that the binoculars can show.

Are 10×50 Binoculars Good For Astronomy?

10×50 binoculars are great for astronomy. They are considered mid-sized and mid-powered, combining versatility with an ability to scan the sky and get great general views.

Unlike some of the larger binoculars on the market, 10×50 are generally easy to hold for most people and do not generally require the purchase or use of a tripod.

This will also help the user to get a consistent, steady image and can be taken on the go.

That being said, with a 10×50 binocular your exit pupil is going to be 5mm.

For night time use this is more than sufficient, but these binoculars will not be able to offer the same views as say, a pair of 10x70mm binoculars.

Those with a larger objective lens, while being larger and bulkier, will be able to provide brighter images at night which may very well be required for astronomical observations.

In this instance, a tripod may however be necessary.

It is generally accepted that the smallest binoculars that would be suitable for astronomy are around 8×30, while the largest that can be comfortably hand-held for longer periods would be around 15×70.

So, 10×50 fit perfectly in the middle making them a good choice for astronomy.

What Are 10×50 Binoculars Good For?

10×50 binoculars have a range of suitable uses and are great for a number of different outdoor activities. They can be used for astronomy or hobbies such as bird-watching and hunting.

However, it is important to consider that there is no perfect magnification for all circumstances and situations.

For this reason, one pair of binoculars is unlikely to be suitable for everyone, or for every context.

This is because it is a fine balance between magnification and image quality; it depends entirely on what you want to see and in how much detail.

So, when it comes to identifying the best binoculars for you, you should think about when and where you will use them.

Is it going to be predominantly in the day, or at night?

Do you want to scan or do you want to be able to zoom in much further?

Nevertheless, 10×50 binoculars are considered ideal in the respect that they are generally not too heavy or large.

What Are The Best 10×50 Binoculars?

Binoculars are a very useful tool for observing; they are generally very easy to use, require no setup, have little to no maintenance and are typically quite affordable.

They are ideal for those looking to get started in a hobby while keeping their costs down.

But what are the best 10×50 binoculars on the market?

If I were to purchase a pair, I would look at either the Celestron Outland X or the Nikon 7245 Action EX Extreme 10×50’s.

Both are available for great prices on Amazon and are some of the most highly reviewed binoculars in their particular category. Clicking on either link above will take you right to their respective Amazon pages to learn more.

But if I had to choose between the two, I would opt for Celestron Outland X.

They are completely fog-proof and waterproof and they come with multi-coated optics and BaK-4 Prisms to ensure you get the clearest of views in all viewing conditions.

Owners report fantastic crisp, detailed views regardless of whether they are being used for astronomy, bird watching, hunting, etc.

The rubber coating makes them durable and well-protected, also ensuring that they fit comfortably in the hands is not likely to slip.

Plus, I personally love the twisting eyecups which enable you to make quick, instant adjustments right when you need to. Focusing and amendments to the eye relief are all possible in a couple of seconds.


There are many numbers to consider when buying any piece of equipment. But hopefully, by now you are aware of the main two regarding binoculars.

For 10×50 binoculars specifically, you’re getting a fair powered pair that are equally not too big in size.

You’ll be able to carry these around with you on the go, for extended periods while focusing on with a clear, steady image.

This makes them ideal for astronomers or other day-time hobbyists.

Looking to the sky you can see amazing views of the Milky Way, impressive nebulae, comets, and some of the most fascinating stars in our galaxy.

On the ground, you would be able to see birds or large game in amazing detail.