How to Choose Binoculars
Wherever you choose to get binoculars, the information below will help you make sense of the myriad options and guide you to some the most important things to consider. For an overview of some of the models in our selection at our store in Novato, one of the best binocular sources in Marin County and the San Francisco Bay Area, see Our Selection.
To learn about more of the binocular related help and services we offer, see our Binocular Homepage.
Bigger and smaller binoculars may offer the same magnification, but larger binoculars perform better in low-light conditions.
What do the numbers mean? (i.e. for an “8x42” binocular)
The first number is the magnification—an 8x42 binocular will make things look 8 times closer. The second number is the diameter of the larger lens (the lens away from your eye), known as the objective lens, measured in millimeters. Larger lenses make for a bigger and heavier binocular, but allow more light to enter the prisms, giving a brighter view in low light conditions (at dusk, or in a deeply shaded forest). Together, the numbers are generally pronounced “8 by 42.”
What magnification should I use? Is bigger better?
For typical birdwatching and general use, most people use 8 or 10 power binoculars (sometimes 6–7 power, occasionally as high as 12 power). While it might seem advantageous to use more powerful binoculars that make distant things seem even closer, there are a number of downsides to increasing magnification: 1) shake from your hands is also magnified, often becoming irritating at 10x or 12x and unusable above that, 2) field of view gets smaller (think of zooming in on a camera - you see less stuff the more you magnify), and 3) brightness decreases. 8x binoculars are the most popular for general use, but many people also use 10x, especially if they have steady hands and spend more time looking at distant, relatively immobile objects such as waterfowl or shorebirds.
What objective size should I use? Is bigger better? Is smaller better?
In short, your choice of binocular size primarily involves a tradeoff between light gathering capacity and size/weight. There are limits to the usefulness of more light—on a bright sunny day, even a small compact binocular may provide bright, clear images and it is only in low light conditions that you will see the full benefit of large objective lens sizes. The quality of the optics also affects the brightness of your image—a top-shelf compact may outperform an inexpensive full size binocular. But to simplify a little, most nature-viewing binoculars fall into three categories:
- Compact (< 30mm): a definite trade off in image brightness for the sake of extreme light weight and compact- to pocket-sized dimensions.
- Mid-size (30–32mm): offer most of the optical performance of full-size binoculars during normal daylight conditions, while offering a size and weight that is generally comfortable to hold and handle, though not pocket sized. This category is becoming increasing popular and our best selling models fall within it.
- Full-size (42mm): generally offers good optical performance even in borderline lighting conditions in a size that is still manageable by most, though some models will seem heavy to some people. The most popular size among serious birders today, though mid-size binoculars have been gaining ground. Larger, 50mm binoculars are sometimes seen, but are generally too bulky and heavy for most people to use comfortably, while only offering a major brightness advantage at dawn/dusk or at night.
Things to look for when shopping for a binocular under $100
- If you can, spend more. You can now find binoculars for $100-$200 that are lightyears ahead of the cheapest models and often include long-term or even lifetime warranties. If you can get something for $140 that will let you see well and last for the rest of your life, that will represent a better value than a $60 headache-inducing, compact pair with dark, cloudy images, and no warranty service when their fragile prisms are invariably knocked out of alignment.
- Try out the specific pair you will buy! The cheapest binoculars are often quite fragile and a shocking number of mail-ordered or clam-shelled binoculars at big sporting goods stores have already been knocked out of alignment in transit. If you haven’t used binoculars before, you may not realize that they are flawed and may think you’re doing something wrong or that that’s how they’re supposed to be. They shouldn’t give you a headache! We have failed to find any <$50 binocular that reliably arrives from the manufacturer in perfect working order: you may get a usable one, but there is a good chance you will get a flawed pair.
- Avoid extreme magnifications. Generally stick with 8x binoculars at this price point. Poor quality glass already results in darker images, and magnifications of greater than 10x will only increase this.
- If you want to use your binoculars while wearing glasses, check the “eye relief” number. Eye relief represents the distance away from your eyes the lenses "should" be to allow you to see the full field of view. Look for 15mm or greater: if the binocular has a 9mm eye relief distance and you wear your glasses 15 mm away from your eyes, you will never get a comfortable view. (Most but not all binoculars over $100 have adequate eye relief, but many cheap pairs do not.) If you want to switch between wearing and not-wearing glasses (or share between two people with different glasses habits), look for a binocular with twist-up and down eyecups, rather than simple rubber cups that must be clumsily folded down around the full circumference of the eyepiece.
Things to look for when buying a binocular from $100–$600
Above $600 or so, most (though not all) binoculars will offer solid mechanics, a dependable warranty, and good optics. The main task then comes from sorting out good optics from better optics from the best optics. But from $100–$600, there are a lot of very good value binoculars—and some to avoid. At these prices, you should be able to get:
- A good warranty. Many companies (such as Eagle Optics, Vortex, Nikon, and Vanguard) offer a no fault lifetime warranty on all their binoculars above around $100. This is more or less expected from the high end binoculars ($1000+) from Zeiss, Leica, and Swarovski, but be aware that you should be able to get at least a several year warranty for any $100+ binocular. This will usually cover most typical repairs, with your only responsibility the cost of shipping the binoculars to the repair facility.
- A size that’s comfortable for you. Once you reach this price range, you have a full range of sizes available to you: there are decent compacts and many good mid-sized (30–32mm) and full-sized (42mm) binoculars in this range. Try out multiple pairs to find one you are comfortable with. Some 42mm binoculars will be too heavy or bulky for some individuals—it’s hard to evaluate this without a personal trial.
- Check the specs: if you’re paying over $100 for a pair of binoculars it should be fully waterproof and fogproof (“nitrogen purged”), have “fully multi-coated” lenses, have twist eyecups (rather than fold-down rubber eyecups), have eye relief of 15mm or more, and have a minimum close focus distance of less than 15 ft. (or ideally less than 10 ft.). These are all basic qualities of good binoculars that are often missing on cheaper pairs, but are uniformly present on high-end models. Once you reach this middle price bracket, it isn’t hard to meet all of these specifications—there’s no need to settle for less.
- Optical quality. Between a $1000 pair and a $2000 pair, the optical difference can be relatively small, especially to the untrained eye. But with mid-range binoculars, almost everyone will see a pretty clear progression from $100 to $300 to $600—the image will appear increasingly bright, vivid, and sharp. You will not find a miracle pair of $100 binoculars that looks better than the best $600 binoculars. It is easy, however, to find a disappointing pair of $300 binoculars that looks like a pair of $120 binoculars. Try out multiple pairs side-by-side, if at all possible—just a few minutes of casual use will weed out the unworthy underperformers.