Binoculars: What do all the numbers mean?
It might look confusing, but binocular and spotting scope sizes and magnifications are actually fairly straightforward.
Binoculars are usually sized by two numbers . You will normally find these on just about all binoculars.
The first is the magnification and the second after the “X” is the diameter in millimetres.
This means that an 8x42 would have an eight-times magnification and each of the front lenses would have a 42mm diameter. (It's not the combined size of the front lenses as we sometimes have folks ask us. You get two lenses of 42mm across. If you're talking to someone about it, it would described as "eight by forty two"
A 7x50 means seven-times magnification and 50mm front lenses and so forth.
You will usually find the size of binoculars on the body or on the focus knob.
This pair of Nikon Travelite binoculars at BINTEL have a magnification of eight times and 25mm diameter front lenses.
Spotting Scopes (and zoom binoculars) usually have a range of magnifications. For example, 20-60x80 would mean a magnification that goes from twenty times to sixty times with front lens diameter of 80 millimetres. An 8-18x42 pair of Nikon Aculon binoculars have a magnification that zooms from 8x to 18x.
A Celestron Spotting Scope at BINTEL showing the size and magnification. This could also be described as being 20-60x80.
Are bigger binoculars always best?
The answer is a “no, not always”.
There are two things to consider. Magnification and lens sizes.
You use binoculars to get in “closer”, so those with the highest magnification would always be the best ones to use, right? On the face of it, yes that would be the case. BUT there are a few things to consider.
First of all, while higher magnification means larger images, it also means a reduced field of view or how far you can see side to side. A reduced field of view can make it harder to spot what you’re looking for, especially for fast moving objects.
One other factor to consider is hand shake. Everyone’s hands shake or move, especially when holding something in front of your face like a pair of binoculars. The higher the magnification, the more noticeable any shake will be. (As you learn the best positions to hold binoculars in, the effects of hand movements will lessen.)
The larger the lens, the more light the binoculars collect and concentrate into your eyes. During a bright clear day, 10x32 and 10x42 binoculars of the same brand and model will produce fairly similar views. When conditions are not so great due to the time of day, weather or where you're trying find birds, the difference in the brighter views the 10x42 present to you will be noticeable.
Larger lenses can also produce more detail in an image as they are simply collecting more information from distant objects. (Bear in mind that higher quality and more expensive lenses can also assist with this as well.)
Is there one size that's "best" for birdwatching?
This is something we get asked about all the time!
The simple answer is no, however if you don't want to read further, we'd suggest a pair of 8x32 for portability and 8x42 for best overall viewing.
There's a lot of debate in the birding community about the right size for viewing our feathered friends. There's a few things to consider. Birds are often moving during the day, either through the air, on the ground or in foliage. This can make them hard to spot and locate.
This means having a wider field of view will let you locate the initially and then follow them as they move about.
You'll also want a pair of binoculars that aren't too heavy as you'll likely need to travel with them. The smaller size also helps with tracking birds and other wildlife, but large enough to capture great views.
Our suggestion is probably 8x42 being a good size for birding for many people. For something more portable, a pair of 8x32 will also do a great job. On the other hand, if you're going to be using them in lower light conditions, the 8x42 might be a better chouse.
Should I go with 10x magnification?
This is a topic of a lot of debate! We often have new bird watchers pop into to see us, and mention they've watched hours of YouTube videos and read dozen of forum posts about what the "right" magnification for bird watching is before making a decision, only to change their mind once they actually try a few pairs of binoculars for themselves.
If you're a more experienced birder and can more readily find and track them, then a higher magnification might be a good option. The distance is also a consideration. For example, if you're seeking pelagic or water birds, these might be a little further away and the higher magnification could well be worth considering.
We often comment to our customers that you're not going to make a mistake - a good pair of binoculars are going to greatly enhance your birding experience no matter which size you choose. It's a matter of fine tuning the selection to what suits you best. This is always something we're happy to chat about at length.
What are image stabilising binoculars?
These are binoculars that have tech inside them that almost totally stops jittery views due to hand shake when using higher magnifications. They are a little more expensive, however well worth considering especially when observing wildlife at long distances.
Kite Image Stabilising Binoculars at BINTEL
Are birding binoculars waterproof? What happens if I get them wet?
Pretty much all the modern binoculars we sell at BINTEL are waterproof. If you get them wet or have water sprayed on them, they won't be damaged. Many of them are also weatherproof. This means they have special coating that help prevent dew of moisture build up on the lenses. No matter what binoculars you use, don't leave them permanently exposed on on say an outdoor table or setting.
Why do some brands and models cost so much? What am I getting for my money?
If you look at the BINTEL website you'll quickly realise we have binoculars that sell for a few hundred dollars up to several thousand.
What you'll notice is that with the higher end brands here at BINTEL such as ZEISS, Swarovski, Leica others, the views through them are crisper, sharper and have brighter colours and definition compared to lower cost optics. You'll still get unforgettable views through almost any pair of binoculars when bird watching, but there's options to improve your experience for the time you spend in the field.
Some ZEISS Conquest HDX Binoculars at BINTEL
Can you help me select the best size and brand binoculars?
Most definitely yes! It's something we get a kick out of here at BINTEL. Despite doing this for more than four decades, it's always a joy to see a customer walk about of here with a new pair of binoculars that we know will give them years of bird watching enjoyment.
Cheers,
Earl White
BINTEL
4th April 2025
