Ultimate Guide To Monoculars

Ultimate Guide To Monoculars

Monoculars are similar to both binoculars and telescopes but have a few different defining characteristics. So what exactly are they? 

Compared to telescopes and binoculars, monoculars tend to be the lesser-known tool of the optical instrument family.

Even though they have a lot of benefits, many people underestimate them. 

Since the tool is very light, small, and compact, you can easily travel with them and use them in different situations such as hiking or hunting. 

If you are interested in learning more about monoculars, this guide will be for you.

We will cover what monoculars are, how they work, and why you should choose monoculars over binoculars. 

This guide will also explain some essential parts of monoculars, such as the lenses, accessories, and maintenance. 

By the end of this article, you will know if this optical instrument is for you. Let’s get started. 

What Is a Monocular?

What Is a Monocular?

A monocular is a type of refracting telescope that magnifies images of distant objects. The optical instrument passes light through prisms and lenses within the body. 

Essentially, if you cut a pair of binoculars in half, you will have a pair of monoculars.

Instead of two viewing tubes like binoculars have, a monocular only has one viewing tube.

They are also quite similar to telescopes but do not have as high magnification power. 

All monoculars will typically have the same parts: an ocular lens, focus wheel, twist eyecup, and an objective lens. 

Monoculars weigh significantly less than binoculars, about less than half.

Even though they have many similar optical properties, they are normally much less expensive than both binoculars and telescopes. 

Another main feature of monoculars is that they produce a two-dimensional image, unlike binoculars. 

History of Monocular

History of Monocular

The history of monoculars largely correlates with the history of binoculars. Since the two instruments use the same optical systems, the two have similar histories. 

Around 1850, Ignatio Porro developed the modern Porro prism binocular system.

Using the same technology, Porro started to develop monoculars in 1860.

These optical instruments had the same prism system that appeared in modern Porro prism binoculars at the time. 

Unfortunately, this line of monoculars soon died out due to a few factors, such as poor materials, unrefined designs, and poor production techniques.

While you won’t find any original monoculars from this line, the optical instrument is still popular today. 

How Does a Monocular Work?

How Does a Monocular Work?

Monoculars work pretty similarly to binoculars and telescopes. These optical instruments can make distant objects look closer.

A monocular works by passing light through the prisms and lenses to magnify the image, making the distant object clearer. 

There are two main kinds of monocular designs. 

The Porro Prism Design

Many monoculars are modeled after the Porro prism design. Developed by Ignatio Porro, this design is prevalent in lots of binocular models.

The design utilizes a curved lens that works with a prism. 

The main job of the lens is to capture light from the outside at far distances. The lens will then take the light and amplify it.

However, when the lens amplifies the light, the image is reversed because of the shape of the lens. This is where the prisms come in. 

After the lens amplifies the light, the prism will take the upside-down image and will invert it.

This mechanism works by using internal reflections to guide the light beam from the objective lens closer together.

This process then corrects the orientation of the image, as mentioned before. 

The prism is typically located between the objective lens of the monocular and the eyepiece lens. 

Monoculars are almost always cheaper than binoculars because monoculars only have one set of lenses and prisms while binoculars have two. 

Lastly, the objective lens tube of Porro prism monoculars is not in line with the eyepieces but is offset, meaning that the prisms are at an angle to the objective lens from the eyepiece. 

The Roof Prism Design

Another design you might see in monoculars is the roof prism design. This design is also popular for binoculars. 

Unlike Porro prism, roof prism designs have two straight lens tubes. This feature makes roof prism monoculars a bit lighter and more narrow than other designs. 

The objective lenses of roof prism monoculars are in line with the eyepieces, unlike Porro prism systems. 

Most roof prism optical instruments use the Schmidt-Pechan prism or the Abbe-Koenig prism.

The main job of these prisms is to invert the coming image and fold the optical path. 

Why Should You Use Monoculars Over Binoculars?

Many people choose binoculars over monoculars; the former is more well-known, which is one of the reasons it is more popular.

However, there are a few reasons why you may want to use monoculars over binoculars. Let’s take a look. 

If You Are Looking for an Affordable Option

If You Are Looking for an Affordable Option

The first and most obvious difference between the two is price.

While the two products can be similar in price depending on the quality, you will easily be able to buy a pair of decent monoculars for cheap.

For instance, you can usually find a pair for around $12. 

Monoculars Are Lightweight

Another main difference between monoculars and binoculars is weight.

Since monoculars only have one viewing tube compared to two, the instrument will be smaller, more compact, and much lighter. 

Many people use monoculars if they want the perks of binoculars but not the added weight.

Monoculars are easy to bring along on a hike or camping trip in your backpack or pocket. The tool will also be hard to damage since it is so small. 

If You Are Visually Impaired

One benefit that monoculars have over binoculars is that they are suited for those who are visually impaired.

For instance, people who only have vision in one eye can easily use monoculars. 

Furthermore, monoculars will work well for those who have different vision in each eye.

Visually impaired people will tend to use monoculars to see everyday things that others can easily see.

Monoculars Work Well for Viewing Art

Monoculars Work Well for Viewing Art

Another common use of monoculars is to view art up close at art galleries.

Sometimes it may be a bit hard to stand as close as you need; this is when monoculars will be helpful.

Art connoisseurs will also use monoculars as magnifying glasses.

You can buy one small enough to fit in your pocket or purse and pull it out when you want to inspect a painting further. 

If You Care More About Weight and Size Than Quality

A monocular may be the better choice if you care more about weight and size than quality. 

If you are doing certain activities such as hiking, camping, or any physical activity, then weight may be more important.

While you can still find high-quality monoculars, they most likely won’t give the same experience as binoculars, which will be something to keep in mind.

Monoculars Work Well for Quick Viewing

Monoculars Work Well for Quick Viewing

If you are not necessarily wanting to spend your whole evening looking through binoculars but only taking a few quick looks at wildlife, monoculars will be the way to go. 

Since they are so light, you can easily whip out your monocular when you want if a bird flies by, for instance. 

Binoculars are more suited to those whose main goal is to view wildlife with a high-quality lens.

Since they are heavier and more expensive, users are typically more intentional with binoculars.

On the other hand, you can pick up some monoculars if you intend only to do some light and quick wildlife viewing. 

If You Want a Tool That Is Easy To Adjust

Monoculars will be a great choice for you if you want a tool that is easy to adjust. Since there is only one viewing tube, you will only have to adjust one lens.

You can simply play around with the focus wheel a bit to clear the image. 

Compare that to a pair of binoculars, in which you would have to adjust the two viewing tubes.

There are three different ways you can adjust binocular settings, which would take longer than adjusting monoculars. 

If You Want a Magnifying Glass

Lastly, you should choose a monocular over a pair of binoculars if you find yourself in need of magnifying glass throughout the day.

While monoculars can do a lot, you can also simply use them as magnifying glass. 

You can throw a monocular in your purse or pocket and whip it out when you need to read some small text. 

Monocular vs Spotting Scope

A lot of people think that monoculars and spotting scopes are the same tools.

Even though they have some similarities, a monocular is an entirely different instrument.

Let’s take a look at some of the main differences between spotting scopes and monoculars. 

Spotting Scopes Have Two Adjustable Rings

Spotting Scopes Have Two Adjustable Rings

One of the main differences that you will find between most monoculars and spotting scopes is that scopes typically have two adjustable rings. 

Monoculars have one main ring, which is called the focus wheel.

On the other hand, you will find two adjustable rings on a spotting scope; the focus dial and the magnification adjustment ring. 

You can adjust the focus with one ring and the magnification with the other. 

Most Spotting Scopes Require a Tripod

Another major difference between monoculars and spotting scopes is that you need a tripod for most spotting scopes.

Unlike monoculars, spotting scopes are designed for tripods. Even though you can handhold spotting scopes, they work best with a stable tripod.

However, monoculars are different in that you can easily hold the tool in your hand.

You do not need to use a tripod when looking through a monocular; the image will be just as clear. 

Spotting Scopes Work Better in Low Light Settings

You will find out quite quickly that spotting scopes work better in low-light settings than monoculars do.

Moreover, since most spotting scopes are compatible with tripods, you can use them to stargaze or view wildlife at night.

Using a tripod will increase the stability of the scope, which will then allow for more light to enter the lens, making it easier to see at night. 

While you can use monoculars at night, they won’t be as good as spotting scopes. 

You May Experience More Neck Pain When Using a Spotting Scope

You May Experience More Neck Pain When Using a Spotting Scope

Since you will need to use a tripod with most spotting scopes, you may be looking through the lens at odd angles.

For instance, most adults will have to look a bit downwards if they use an angled spotting scope. 

If you are using a regular spotting scope, you still may have to bend down a bit and move your head to get the perfect angle. 

This could become a problem if you plan to use the spotting scope for more than an hour or so.

You could easily experience neck pain if you are in odd positions for a long period.

If you are looking for an instrument for long-term use, you may want to keep this in mind. 

In contrast, you won’t have to position yourself in any odd angles when using a monocular. Instead, you can simply bring it up to your eye and enjoy the view. 

Monoculars Are More Compact

While this won’t necessarily be true for all models, most monoculars will be more compact. 

If you want an optical instrument that you can easily throw in your bag, a monocular will be the way to go.

However, you will typically have to bring a few extra pieces of equipment, such as a tripod along with you. 

For this reason, monoculars will be great tools if you want something light to bring along. However, it might not be as easy traveling with a spotting scope. 

Spotting Scopes Require Setting Up

Another thing to keep in mind if you are trying to decide between the two is that it might take a bit to set a spotting scope up. 

While you can simply pull out your monocular, you will have to take a few minutes to set up the tripod and spotting scope.

Furthermore, you will also have to fiddle with the settings more to make sure the image is bright and clear.

Spotting scopes are not quick tools that you can have access to in a few seconds. 

Spotting Scopes Work Better for Hunting

Spotting Scopes Work Better for Hunting

If you are an avid hunter, you may be happier using a spotting scope instead of a monocular.

Even though monoculars are easy to travel with and quick to set up, they aren’t as powerful as spotting scopes are. 

You will be able to see further distances with a spotting scope. When it comes to hunting, a spotting scope is a way to go.

You may miss spotting your prey if you use a monocular.

Monocular Lenses

Monocular Lenses

In this section, we will review the two lenses that each monocular has. These lenses include the objective lens and the ocular lens. 

Objective Lens

Each monocular has an objective lens. This lens is the closest to the outside and is the lens furthest from your eye. 

The main job of the objective lens is to gather light from the outside. The lens then focuses the light to produce the image. This image then travels to the ocular lens.

The objective lens is the most important part of the monocular. It is the most complex piece of the instrument. 

Overall, the objective lens determines a few different characteristics of the produced image.

The objective lens determines the primary formation of the image, the total magnification, the image quality, and the overall resolution. 

Ocular Lens

The ocular lens is the lens closest to the eye. You can also call this lens the eyepiece lens. 

What the ocular lens does is magnifies the image. The lens will pick up the image from the objective lens and convert it to a bigger image that is easier to see. 

Monocular Accessories 

Monocular Accessories 

Now that we know how monoculars work and how they are different from binoculars and spotting scopes, let’s see what kind of accessories you can use with them. 


One of the most important accessories to have for your monoculars is a strap. Having a strap will ensure that you won’t drop and break the tool.

Furthermore, a strap will be handy to have while hiking or hunting. 


Even though they aren’t as popular for monoculars, you can buy a tripod for the optical instrument.

Tripods will be the best to use in low light conditions or if you are going to be looking at the same spot for a while.

Tripods will help keep your image stable and less shaky. 

Smartphone Adapter

Another helpful accessory you can get is a smartphone adapter. With this adapter, you will be able to take photos and video through the monocular eyepiece.

This accessory will be great to bring along for wildlife viewing or a hike. 

Not only will you be able to enjoy the views through your monocular, but you can share the views with other people. 

Lens Filter

You can also get some lens filters for your monoculars. A popular lens that people buy is haze filters.

These yellow filters will increase the image quality in smokey, hazy, or foggy conditions.

Even when the weather is not cooperating, these filters will still allow you to take your monoculars out and get some good views in. 

Monocular Pouch/Case

An important accessory to have is a monocular pouch. Having a pouch is helpful when you don’t want to carry the monocular around your neck anymore. 

Furthermore, a case will help protect the optical instrument when you are not using it. The pouch will prevent scratches, dents, and damage. 

Monocular Maintenance 

Monocular Maintenance 

Even though monoculars are generally less expensive than binoculars, they can still be quite expensive.

For this reason, there are a few things you should do to maintain your monoculars and prevent damage. 

  • Use a strap. The best way to prevent costly damage is to use a strap. This way if the monocular slips in your hand, it will not fall to the ground. You will easily be able to find a strap at your local photography store or online. 
  • Store your monoculars in a case. You should always store your monoculars in a case when you are not using them. Storing them haphazardly on a shelf could lead to unnecessary costs for repairing or replacing the optical instrument. 
  • Handle them with care. Another thing to remember is to handle your monoculars with care. Avoid holding onto them just by the strap, placing them on a chair, leaving them in the car, or using them without a strap. 
  • Avoid using them in the rain. While you can use your monoculars in light rain, you should avoid using them when it is pouring. If your pair does get wet, make sure they are completely dry before you store them. Otherwise, the inside could have water damage, or some parts could begin to rust. 
  • Clean your lens regularly. If you use your monoculars quite often, you should remember to clean the lens regularly. You can use lens wipes, an air blower or lens cleaning brushes to do this. Make sure to remove all of the dust and debris from the lens every time you clean it. 
  • Use the lens cap. One of the most important parts of lens care is using the lens cap. Whenever you are not using the monoculars, put the lens cap on. Doing so will prevent scratches and dust from dirtying the lens.


We hope that this ultimate guide to monoculars has helped you learn more about this helpful tool. 

A monocular is a type of refracting telescope that magnifies distant objects by passing light through lenses and prisms.

There are two basic kinds of monoculars: Porro prism monoculars and roof prism monoculars. 

There are a few reasons why you should use a monocular over a pair of binoculars.

Monoculars will be a good choice if you are looking for a more affordable and lightweight option.

Furthermore, monoculars are good for quick viewing and easy adjustments. 

While many people think spotting scopes and monoculars are the same, they are quite different.

Most spotting scopes require tripods and will take longer to set up. Compared to spotting scopes, monoculars are much lighter and are more compact. 

Overall, monoculars are great tools for those looking for an easy-to-use tool in which you can set up quickly.

You will be able to fit them in your bag and whip them out to view wildlife passing by.