How to choose the best lightweight binoculars for bird watching

If you are searching for compact binoculars for bird watching, it’s probably because you would like a small, lightweight pair of optics that combine easy portability with quality viewing. This article will talk about the qualities of compact binoculars and how they differ from full-sized ones.

It is possible to find birding binoculars that are both light and great for viewing birds over short and long distances. What you need to look for in compact binoculars is not only the size and weight but the overall quality of the image. For this it is best to take into account field of view, magnification and brightness. If you need small, light binoculars for travel then waterproofing and toughness are also considerations.

Are small binoculars any good for birding?

The good news is that there are plenty of affordable options that will not sacrifice the standard of images. They will be light and so easy to fit in your bag that you will be more likely to take them with you on more occasions, increasing your value for money as well as your enjoyment.

Like all optics, compact binoculars have advantages and disadvantages. We can guide you through them to weigh up what is the best choice for your requirements.

Compact binoculars are a good option for when a full size pair is just too big, like when you are out biking, hiking or backpacking. Some people like to have a spare pair to supplement their primary pair, to keep in a car glove box, for example.

Is your primary intention to use your binoculars while out on lengthy hikes? If you need to carry them over long distances, a lighter, compact pair might be preferable.

What should I look for in small binoculars?

Overall design

The smallest binoculars tend to be of a roof prism design. This style of binocular is more compact. The reason for its smaller size is the way the lenses at both ends line up with each other. Consequently, the barrels are naturally straight and narrow.

In contrast, the lenses at either end of Porro prism binoculars are not aligned in a straight line. Because one end is offset from the other, in a kind of zig zag shape, the barrels are wider to accommodate the internal configuration.

There is another option, called the reverse Porro prism. This, as the name suggests, is the opposite setup to the Porro prism. Reverse Porros have their front lenses closer together than the eyepieces, enabling the body of the binocular to be more compact.

Porro prism vs roof prism binoculars: which is better for birding?

While working out how to choose birding binoculars, there are some considerations that are common to binoculars of all sizes and some considerations that are more specific to compact binoculars.

Recommended considerations, common to all sizes:

• Wide field of view
• Appropriate magnification
• Effective objective lens size
• Comfortable and compact
• Waterproof and fog proof
• Close focus distance

For more detailed discussion of how these will affect your choice, please visit our in-depth guide here.

How to choose the best binoculars for bird watching

How to choose the best lightweight binoculars for bird watching

Here are the more specific requirements to bear in mind when choosing compact binoculars for bird watching.

Field of View

You can still get a decent field of view in a compact binocular. Field of view depends on the magnification, which is determined by the ocular lens next to your eye, and the design of the eye piece.

So even if you have a smaller objective lens, as in a compact binocular, you can still enjoy the same field of view as a model with larger objective lenses. As long as you maintain a modest magnification, the width of the field of view should not be compromised.

Eye Relief

Eye relief measures the gap between your eye and the lens closest to your eye. It is important to get the right distance so that you get a full field of view.

The smaller size of compact binoculars makes it more of a challenge to find a pair with the appropriate eye relief if you wear glasses. Their reduced size is less able to accommodate the adjustable eye cups offered by larger models.

It’s best to look for an eye relief of at least 14mm or 15mm, depending on the thickness of your glasses and how close to your face they sit. If you have a larger face then you may need to look for eye relief upwards of 15mm.

Focusing

Reducing the size of the binocular can make it fiddly to use the focus knob. Be sure to check that the size and design suit you. Can you use it easily and quickly, even if you are wearing gloves?

Waterproof and fog proof

Most compact binoculars over $100 will feature the internal seals that ensure waterproofing.

Armoring

A rubberized outer coating protects the binoculars and makes them easier to grip, especially in extremes of temperature or wet weather.

What are compact binoculars?

A compact binocular is small enough to be easily carried in a purse or pocket. When looking at specifications of binoculars, you can tell what size it is by looking at the second number in the name of the model.

The second number, for example the 32 in 7×32, denotes the size in millimeters of the objective lens.

Generally, the three size categories of binocular are:

• Compact – less than 30mm
• Midsize – 30-40mm
• Fullsize – 40mm +

Some people would take this even smaller and say that only binoculars with a second number smaller than 26 or 28 can be called a compact binocular.

Compact binoculars for birding – the advantages

Pros of lightweight binoculars

• reduced size
• convenient to keep in your bag or even pocket
• lighter to hold and use for a long time without feeling tired
• lighter to carry in your pack on hikes
• less cumbersome to carry around your neck when on the move
• maintain moderate viewing power

Size

An objective lens of a small diameter reduces the overall size of the binocular, thereby increasing portability. The smaller dimensions make the instrument easier to fit in your bag, especially once you fit it into a protective case as well.

Weight

It is more comfortable to carry lightweight binoculars and to hold them up to your eyes for viewing.

Price

Downsizing dimensions can mean upgrading in quality. Buying compact binoculars can allow you to afford a more premium product.

Image quality

Because it is easier for manufacturers to produce smaller sized lenses to a higher optical standard, premium compact binoculars can include features that correct distortions and aberrations more evident in larger lenses.

Compact binoculars for birding – the disadvantages

Despite all the benefits of compact binoculars, it is only fair to weigh up the compromises that you make when reducing in size.

Cons of lightweight binoculars

• may be less comfortable for longer viewing sessions
• lack some features
• larger magnifications are even more difficult to hold steady

Field of view

As long as you maintain a modest magnification, the width of the field of view should not be compromised.

Brightness

When the size of objective lens decreases, so too does the amount of light entering the binocular. This impacts the brightness of the image.

Compact binoculars, even with their smaller objective lenses, maintain brightness equal to larger binoculars in ordinary daylight and quite far into twilight. But in much lower light conditions a reduced brightness will become apparent.

Resolution

Similarly, due to their smaller objective lens diameter, compact or lightweight binoculars are unable to match mid or full size binoculars with larger objective lenses when it comes to resolution. For the viewer, the effect is a loss of sharpness and finer details.

Eye fatigue

With any binoculars, it is important to get the correct viewing placement of your eyes in front of the ocular lenses. This not only ensures you see the most optimal view (no black circles!) but it helps to keep your eyes fresh.

The exit pupil is the light beam that comes out of the eyepiece to go into your eye. When your eyes are not quite centered behind the eyepieces you may feel eye strain. Compact binoculars have a smaller exit pupil, so it is even more important for your eyes to be placed correctly.

As you build up time and experience using your binoculars, the risk of this reduces.

Adjust your binoculars to suit your face and vision

In addition, ensuring that the binoculars are properly set up in the correct placement for your face and eyes will also help.

The measurement between the two pupils of your eyes is called the interpupillary distance. The hinge in the middle of the binoculars allows the width to be tailored to suit your interpupillary distance and make sure that the ocular lenses are centered in front of your eyes.

We explain how to do this here:

Adjusting new binoculars: how to set up and focus binoculars for bird watching

If you spend long hours using your binoculars, though, it may be appropriate to select a full size pair for more comfortable sustained use.

Steadiness

As with a full size binocular, larger magnifications are more difficult to hold steady and prevent a shaky image.

Though holding a lighter instrument may at first feel more comfortable and less fatiguing, the lightness and compactness exacerbate image shake.

For this reason, 8x is probably the maximum magnification we would recommend in a compact binocular.

How to choose the best lightweight bird watching binoculars for travel, backpacking and hiking

People who are buying birding binoculars for travel need a pair that will be lightweight and compact, but with full functionality.

If you are making the extra space in your luggage for them and carrying the additional weight (within an airline weight allowance too), then it’s important that the quality of viewing makes it worth the effort.

When backpacking, you’re likely to be carrying the binoculars for longer periods of time and be limited for space in your bag.

A light, compact sized pair will be more comfortable and practical, as well as adding to your enjoyment of being immersed in the natural environment.

The best travel binoculars for bird watching: top features

Extra considerations when looking for the best birding binoculars for backpacking or a long trip:

• heat
• dust
• variations in temperature
• additional moisture and humidity

Most good quality binoculars feature waterproofing and fog proofing. Internal o-ring seals achieve this by stopping any moisture or dust from entering.

Cheap traveling birding binoculars may not meet all of these standards, risking erosion of the optical elements inside.

Additionally, look for binoculars that have been nitrogen purged to remove air. These guard against moisture forming on the inside of the lenses when temperature or humidity variations occur due to changes in location or altitude.

On the exterior, many good compact binoculars have a synthetic rubber armor over the body of the binocular. This protects them from accidental scratches or scrapes.

The rubberized coating also makes them easier to grip in damp weather.

Best travel birding binoculars: on the move

A good padded case will protect them not only from knocks and scrapes, but also from UV rays which can cause damage over extended periods. Keep your binoculars out of the sun as much as possible by storing them in a sturdy case when not in use.

It’s also worth making sure you have a well equipped cleaning kit. This is important, especially if your destination is likely to be dusty and hot.

Wiping off dust and debris using sympathetic and effective materials will preserve your binoculars. It also keeps the mechanisms functioning correctly.

Choosing the compact lightweight binoculars: next steps

We hope this article has helped you to understand how the best lightweight bird-watching binoculars differ from full-sized binoculars. It’s important to keep in mind what your needs are and be clear about what exactly you are looking for.

You want to make sure that your compact binocular is an all-around good quality product for any situation. It should have a wide field of view, appropriate magnification and reliable brightness (which determines how clear images are). If you need small, light binoculars for bird watching and travel, then waterproofing and toughness should be considerations.

We’ve taken these considerations into account in our article on the best compact lightweight binoculars, where we outline the top choices in this category.

The best lightweight compact binoculars for bird watching