How To Choose Binoculars For Plane Spotting (Best UK Guide)

If you are one of the millions of people around the world who enjoy watching aeroplanes or spotters as they are known, and you want to take your hobby to the next level then read on. 

We have put together all the information you are going to need to get you the clearest view of every plane you spot from here on in. Or maybe you’re planning to visit an airshow and want to get the best from the experience. We will give you all the best advice on what to look for in the binoculars of your choice.

What Do The Numbers Mean On Binoculars?

The first thing you’ll notice when looking at binoculars are the two numbers separated by an x, these are the magnification and objective lens diameter. For example 10×42, this means the binoculars have a magnification of 10 times and an objective lens of 42 millimeters. The lenses have different names depending on their position in the binocular.

The objective lens is the lens closest to the object you’re viewing, the lens closest to the eye is the ocular lens. If your objective lens is too small, the binoculars will not allow enough light to enter and your image will be dark. 

What Is The Magnification Of Binoculars?

So the first number followed by the x is the magnification value of that particular pair of binoculars. For instance 10×42 means the magnification is 10 times, which in simple terms means the image will appear to be 10 times closer through the binoculars than it actually is.

What Is The Objective Lens Of Binoculars?

As we said earlier, the objective lens is the lens closest to the object (the larger lens at the front of the binoculars) and the second number in this case 42 gives us the size in millimeters of the diameter of the objective lens. So in the above example of 10×42 the 42 is the size of the objective lens – 42 mm. The size of the objective lens also affects the field of view.

What Is The Field Of View?

The field of view is the area you can see through the lens, this includes the peripheral view as well as the view straight in front of you. The larger the field of view is, the easier you will find it to locate the object you are looking for (in this case the jet).

What Is The Best Size Binoculars For Plane Spotting?

Binoculars are classified into three size groups which are determined by their objective lens size. The sizes are;

• Compact
  The compact size range is from 20 to 25 mm objective lens
• Mid-Size
  Mid-Size binoculars range from 30 to 42 mm
• Full Size
  Full size binoculars are anything above 42 mm

It can be slightly confusing because the sizing has little or nothing to do with the actual size of the binoculars, just the objective lens size. With that said, most modern binoculars are far smaller in size than their earlier counterparts, and depending on the type you choose, they’re not as weighty as they used to be either.

We have found that compact models are inadequate for plane spotting, the image is too dark, and the field of view is too narrow to spot planes in motion. For day time plane spotting including airshows, an objective lens of between 32 and 42 will be your best choice, possibly 8×32 or 10×42 will be great choices. However, if high flying planes are your thing, you’ll do better with an objective lens of 42 to 50 mm. Possibly 16×50, these will give maximum magnification and a great deal of light too.

Image Stabiliser

 You will find with magnification that high you’ll benefit from using a stand or tripod to prevent a shaky image, or opt for an image stabilising pair of binoculars. Image stabilisers take account of the natural shake that we all get when holding fairly large and weighty items out in front of us for some time. Image stabilising was developed for the camcorder market and binoculars have benefitted from this technology. The mechanism counteracts the shakes to give you a clear, bright image. The only problem with image stabilisers is they need batteries to make them function, which can run out at any time, and batteries add weight to the binoculars.

Tripods

A far cheaper, and easier alternative to image stabilisers is to use a tripod. These attach to the binoculars via a small screw set up that supports the binoculars, leaving your hands free, and no blurry image due to shaking. This works well with all magnifications, but it’s recommended for all binoculars with a magnification greater than 10x.

The drawback with a tripod is they are usually too low to look through the lens comfortably. The way to combat this is to place a chair in front of the tripod then you will be set up in a comfortable position for some serious plane spotting.

So the magnification you choose will be very much dependent on the way you intend to use your binoculars. 10x and below for hand held binoculars or if using a tripod or image stabiliser, there are binoculars available up to 20x or even 30x, but we would suggest that 15x will be sufficient.

Best Prism Types For Plane Spotting

This really is a matter of choice, and if you’re new to the world of binoculars might seem somewhat daunting, but it’s simple once you get your head around the two types of binoculars available.

Porro Prism Binoculars

These have been around for a couple of centuries, well, the design has. It’s the typical binocular design, narrow end where the eyepiece is, widening out towards the middle, then getting even larger at the objective lens. The reason for the large design is all to do with the arrangement of the prisms inside which enable the image to be magnified, illuminated and upright.

The system works with two prisms for each lens that are aligned in a special way to achieve the clearest, brightest image and then turn it back up the correct way for our brain to see it the right way up. The prisms are aligned at angles to each other hence the large size midway which is to house the prism alignment.

Roof Prism Binoculars

Roof prism binoculars use a different system which allows them to be housed in a smaller casing. This is why they are so much smaller than Porro prisms. They look like two straight tubes, connected at the centre by the focusing knob. Roof prisms are more robust than Porro prisms and will take far more punishment and still work correctly.

Even the largest diameter lens on a pair of roof prism binoculars will be far smaller than their Porro prism counterparts. The catch is due to the internal design, roof prism binoculars are more expensive than Porros, but they are far smaller and weigh far less too.

Do You Need Waterproof Binoculars For Plane Spotting?

In our opinion you need waterproof binoculars whatever activity you are taking part in. Here in Great Britain the weather changes constantly, and what can start as a sunny August morning can turn into the wettest August day on record by teatime. So inevitably you are going to get caught out by the weather at some time.

Waterproof binoculars are relatively inexpensive and make good sense anywhere but especially in the UK. Choose a pair with an IPX rating of 6 or above as this will give you all the waterproofing protection you are likely to need.

Anti-Fogging

Anti-fog binoculars are made by removing all of the oxygen from the tubes and replacing it with an inert gas like nitrogen or argon. As these inert gases contain no moisture they are unable to fog during quick temperature changes. Another bonus of anti-fogging and waterproofing is if no water or air can get in, nor can any dust or debris, keeping your binoculars with a clear view at all times.

Rubber Coating

Having binoculars with a rubber protective coating makes a lot of sense. Accidents happen and at some point we all drop or knock our binoculars against something solid. Rubber coatings protect your binoculars against such impact damage which can be very useful when out spotting.

Lens Coatings

When it comes to buying binoculars for plane spotting, a fully multi-coated lens is essential. This is as near to the top of lens coatings as you can get and will cut down on glare, improve brightness, contrast and light transition.

Best Binoculars For High Altitude Plane Spotting

As we said earlier, any magnification above 10x will result in a shaky image unless you can master the use of a tripod or you have a pair with image stabilisers fitted. With that said, most people can usually cope with 12x magnification with only a slight shake, the trouble is, the higher the magnification, the less light will enter the lens, making the images seem dark.

Zoom Lens Binoculars

Zoom lens can be useful, as you can search for the plane through 8x or 10x magnification and then zoom in to get a closer look. The numbers on zoom lens binoculars look slightly different to ordinary binoculars, a typical zoom binocular number looks like this 10-30×25. This means the starting magnification is 10x but you can zoom in to 30x magnification with an objective lens of 25 mm.

The problem we’ve noticed with these zoom lenses is that the image loses its crispness when zoomed in. The possible reason for this could be why hardly any of the really top companies have designed a pair of binoculars incorporating a zoom. As there is always one exception to this rule, we have found Bushnell makes an acceptable zoom lens binocular that works well. But they are limited to 22x magnification which is good but probably explains why others with higher zoom mags are not so clear.

High Powered Magnification Binoculars

The thing to remember here is that as the magnification increases, so should the objective lens diameter, because if it doesn’t you will lose light when trying to see the image. For this reason if you are going for a 25x magnification, we suggest nothing less than a 100 mm diameter objective lens size. This will give you a bright image even in low light conditions. A 20x magnification should be accompanied with a 50mm objective lens.

Best Binoculars For Plane Spotting Checklist

To give you a quick summary of the information contained in this article and help you choose the best binoculars for plane spotting at a glance;

• Magnification
  We have found that for general plane spotting and air shows a magnification of 8x, 10x or a maximum of 12x is best. And for high altitude plane spotting we recommend 10x to 12x unless you have a tripod or image stabiliser in which case 20xor 25x is good but don’t forget for best image results the higher the magnification is you will need larger diameter lenses which increases size and weight.
• Objective Lens
  An objective lens diameter of 42 is sufficient on any magnification up to 10x but above 10x you will need to increase the objective lens size for instance 25x magnification will need a 100 mm diameter objective lens for a bright enough image to be seen.
• Fully Multi-Coated Lens
  For reducing the glare this is a must. Also to improve brightness, contrast and light transmission.
• Image Stabiliser And/Or Tripod
  With any magnification above 12x you are looking at the image shaking unless you use a tripod or have an image stabiliser installed. Remember that image stabilisers not only need regular battery changes, but also increase the weight of your binoculars.
• Weight
  If you are planning to be holding the binoculars for any length of time, they will feel heavier than they actually are. So go for something relatively light weight if possible. Obviously as the magnification and objective lens diameter increase so does the weight.
• Size
  As we are recommending a minimum of a 42 mm objective lens, this puts you into the full size range of binoculars. But that doesn’t necessarily mean large, bulky, cumbersome binoculars. There are many (thanks to modern technology) that are quite powerful and yet relatively small in size.
• Waterproofing
  Always a wise decision to choose binoculars that are waterproof. Especially in the UK with our ever changing climate.
• Fog Proofing
  Well worth considering because moving from the warmth of the car to the cold of the outdoors can cause untreated lenses to fog up. Making plane spotting impossible until the fogging clears.
• Prism Types
  If you are a little clumsy, roof prisms will be the best choice for you as they are far more robust that Porro prisms that can get knocked out of alignment fairly easily.

Frequently Asked Questions