Gimmick Free Binoculars Part 1

The absolute best advice I can give you when you’re buying a binocular is to…well, buy a binocular.

Let me explain: you’re likely to get the most use and enjoyment out of an optical instrument that is exactly that—a binocular, with no gimmicky features like zoom or image stabilization added. No extraneous bells and whistles, no superfluous “improvements” intended to enhance its performance or, more likely, impress the potential buyer.

To put it in Zen-like terms, you want a binocular that truly wears its binocular-ness, with no other aspiration than to let you see faraway things closer in the best possible way.

I know this runs counter to current conventional wisdom, since these days we want our widgets to do more, to multi-task like we do, to give us something else besides what they were originally designed to do. Take refrigerators, for example. Why just keep things cool when your Wi-Fi fridge can now text you when your milk passes its expiration date, or if you’re low on pickles? 

(In case you were wondering: yes, there is now a Wi-Fi binocular, complete with internal computer, digital video camera, digital zoom, night vision, compass, and if I’m not mistaken, it will text you when you’re low on pickles. And no, you do not want this binocular, regardless of how pickle-centric your life is).

What you DO want is an optic that puts all its emphasis where it belongs—not in conspicuous features designed to impress, but in those comparatively mundane components that deliver awesome optical performance, most notably the glass and its optical coatings that are the heart and soul of a quality binocular. That means no zoom, digital camera, image stabilization, night vision, “ruby” lens coatings, Wi-Fi, compass, GPS, or anything else manufacturers or, to be more precise, their marketing teams, dream up.

Let me be clear: there may be instances when these add-ons make sense for specific users and circumstances, but in general when you add one of these gimmicks you take away something of higher value to maintain an attractive price point (it’s usually glass quality that suffers) AND you usually add weight to the binocular, which is exactly what you don’t want to do. 

Given that these added features are often useless and even counterproductive it’s remarkable that their popularity persists, so proceed with caution as you approach your purchase decision. In Part 2 I’ll talk about a few of the more popular “enhancements” and why you should ignore them if you want the best possible viewing experience with your new binocular.

Gimmick Free Binoculars Part 2

In the previous post I laid out the case for simplicity with your optics purchase—avoiding dubious “add-ons” that more often than not get in the way of your viewing experience. Now let’s take a closer look at a few of the more popular “features” that you would do well to avoid:

Zoom (or continuous variable magnification)

You would assume that the ability to zoom in (from 8x to 24x, for example), to get an even closer look at your subject, would be a handy addition to an optical instrument—and manufacturers have responded to that logical assumption by providing numerous zoom binocular models which you’ll see on any visit to an online optics emporium. What you won’t see is a zoom model from any of the Big 3 high-end guys—Zeiss, Leica or Swarovski—and that should tell you something. Zoom binoculars are rife with optical downsides caused by the mechanical requirements of zooming, rendering them unacceptable to manufacturers with impeccable optical standards. With a zoom the field of view is invariably narrow even at the lower end of its magnification range, and by definition gets narrower still as you zoom in (making it likely you’ll use the binocular mostly on the lower setting). Overall the optical quality suffers by the additional glass elements required for zooming (more glass surfaces for light to pass through) and so does the all-important weight. Zoom all the way in and yes, you’ll see an apparently larger and closer…something, but it’ll be blurry, dark, and not very satisfying. Trust me, skip the zoom.

Image Stabilization

Image-stabilized (IS) binoculars are bafflingly popular and will likely remain so regardless of any efforts to discourage their use. I’ll admit the idea is appealing: make a binocular with a higher magnification than a pair of hands can reasonably keep steady, push a button and presto! The inescapably shaky image caused by the high-magnification of hand tremor is now locked and…stabilized! What could be wrong with that?

Plenty, unfortunately. While there have been some improvements over the years, IS binoculars tend to be bulky, unwieldy and heavier than compatible non-IS models—not the kind of thing you’d want to take with you for a day in the field. Plus the IS feature runs with the help of batteries (usually 2 AA) and is a real battery hog and thus a significant additional expense over the life of the optic. So not only do you have to carry a heavier binocular, you have to also bring some spare batteries.

Again, when image stabilization is added to a binocular something has to be taken away to keep it affordable—meaning that manufacturers spend money on IS and NOT on quality optical glass. The result is that the image stabilization works like a charm, but the image being stabilized is inferior to comparable binoculars. This may be acceptable for marine and astronomical applications but for birding and other nature observation where getting a bright, sharp image is critical you’re better off being your own (battery-free!) image stabilizer.

Digital Camera Binocular

I love binoculars and I love digital cameras (I’m not much of a photographer—the camera in my iPhone 6 is good enough for me!) I love espresso too, but I wouldn’t recommend a bino-espresso maker combo, and as far as I’m concerned a digital camera binocular makes just as much sense. 

Which is not to say you can’t find bino/camera combos—there are plenty of them out there, a response to ongoing consumer demand because it seems like it would be a good idea to shoot a photo of what you’re looking at through a binocular.

Oh, but that’s not what you’re doing with the current crop of digital camera binoculars. Each component of this ill-advised optical hybrid uses its own lens, so what you see is not what you get. In addition, from what I’ve seen you’re getting the worst of both worlds—an inferior camera awkwardly straddling a substandard binocular, giving you a dreary view and mediocre photos. Can you tell I’m not a fan?

Obviously the better way to go is to buy the binocular and camera separately, allowing you to upgrade either one individually as your circumstances and finances warrant. If you still insist on combining the two, there are devices on the market that enable you to attach a smartphone-with-camera to a binocular—though why you would want to I have no idea.

The Most Important Binocular Term

You can ignore most of those technical terms like “twilight factor,” “brightness index,” “chromatic aberration,” “aplanatic refraction” and the like—pay close attention to the weight.

Actually, I made up “aplanatic refraction”, but when you’re buying a binocular in order to enjoy birds and other things in nature, it’s every bit as useful at the other three.

“For the most ideal viewing of everything from backyard birds to gargoyles on the tops of European gothic cathedrals, a binocular with an aplanatic refraction ratio under 8 is strongly advised.”

It’s not that these tech terms associated with optics are bogus—all of them (well, except “aplanatic refraction”) do illustrate something about the binoculars to which they are applied. But they are largely unnecessary to your purchase decision (especially if you’re a first-time buyer) but worse, they are can be counterproductive in that they add to the confusion and the general level of “noise” surrounding optics and a buying process that could and should be simpler than it often is.

Let’s take “twilight factor” as an example—and we’re not talking about the ability of a specific cute teenager to attract the attention of a similarly cute teenage vampire.

If you’re researching optics on the internet you’re likely to see “twilight factor” among the optical performance terms bandied about. Historically it has been used as an indicator of how comparatively well a binocular will perform in low light, and you can calculate its value on any given binocular by the following formula (get out your slide rules, folks):

Multiply the magnification by the objective lens diameter (i.e. multiply the first and second numbers of the “optics formula”) and take the square root of the product. So for a 7 X 42 binocular multiply 7 X 42 (294) and take the square root of that (=17.15). So the twilight factor of a 7 X 42 binocular is 17 (rounded off).

“Wow—17? I’ll take it!”

Seriously, calculating twilight factor successfully may get you a higher SAT score but it won’t help you buy a binocular. In my many years of selling optics I have never had to refer to it during the sales process—although I was often asked about it during optics workshops by attendees who had seen the term while researching optics online.

The same is true for all those other terms and specs that do tell you something about a binocular but add little or no value to custom fitting that binocular to you.

So…what term(s) should you pay attention to? My top 3 are weight, weight and weight.

“Weight” is my favorite too-often-neglected binocular spec. How much weight you’re holding up to your eyes and around your neck makes a HUGE difference in the enjoyment of your binocular (much more than the square root of anything), and thus how often you actually take it out and use it. I’ve seen too many binoculars gathering dust, despite stellar specs, simply because they were too heavy for the user to enjoy.

On a couple of occasions, over my strong objections, customers have purchased expensive 50mm objective (second number in the formula) optics because a “friend” told them “they’re the brightest ones around,” and yes, they do look bright for the few minutes of quick inspection they undergo (I sold binoculars for a nonprofit conservation organization, so sales, even those of which I didn’t approve, helped fund the mission work of the organization). But sometime after purchase they returned, sheepishly, to buy smaller, less-heavy optics (unfortunately the number of people who bought optics against my advice, only to later regret it, could fill a large birding tour bus).

So…forget all the other terms and specs—the brighter, sharper, better binocular is the one that you bring with you and use rather than leave at home or in your car. The $300 binocular with the agreeable weight that is pleasant to use is superior to the $600 heavier binocular that you leave behind—despite what their specs tell you.

So how much should a binocular weigh? I don’t know…how much should a person weigh?

Which is to say there’s no one answer. “Light weight” full-sized (obviously most compacts will be light) binoculars will weigh from around 16 oz. to around 22 oz. Over 30 oz. and they’re going to feel heavy in the hand and up to the eyes but for some people that won’t be a problem. Around or over 3 lbs.? Well, good luck with that. 

I recommend never buying a binocular over 2 lbs. without an extended tryout first. Of course this might be a problem with the diminishing number of brick & mortar stores where optics are sold by knowledgeable salespeople, but certainly this is the preferable option.

Most reputable online optics dealers have expert customer service help and liberal return policies, so after answering all you questions they’ll send your choice (or even your top 3!) which you can try out and return if you’re not satisfied—or if you like the binocular but decide it’s too heavy.

Whatever you do, spend lots of quality time with your new binocular before you buy—if it’s the right choice you’re going to be holding and wearing it so much your friends won’t recognize you without it!

No 12 X 50's, Please

(This post assumes a basic familiarity with the concepts of magnification and objective lens diameter as depicted by the common mathematical formula associated with all binoculars—8 X 42, 7 X 35, etc. If you need a refresher see “The Optics Formula: An Introduction” elsewhere on this site.)

Recently on a well-known and well-respected optics information website someone asked the following question (edited for clarity): “I have about $100 to spend, and I’ve been looking at both an 8 X 40 and 12 X 50. Which one should I buy?”

Where to begin.

OK. Ever the scrupulously-fair optics information provider, the website answered the question by laying out in meticulous detail the pros and cons of both the 8X and 12X so that the questioner could make an informed purchase decision. 

Here’s the deal, though: there are no “pros” to a 12X binocular. None. (“50” is problematic as well, but that’s for another post).

Yes, the 12X makes whatever it is you’re looking at appear 12 times bigger or closer, but at way too steep a price in terms of image quality and viewer experience. Brightness, field of view, depth of field and image clarity all suffer. 

Buy a 12X binocular and pretty soon you’ll stop using it. Guaranteed.

Bear in mind that while you’re multiplying the image that you’re looking at by 12 times, you’re also multiplying your hand tremor (yes, Nerves-of-Steel Guy, you have hand tremor) and any other bodily movement (heartbeat, breath, robust yodeling, etc) by 12 times as well. So not only can you NOT steady the image enough to get a good look, you’re blurring that image as well, making it extremely unlikely you’ll be able to discern important detail.

And the ability to discern detail is one of the major reasons we buy a binocular.

Hang a standard eye chart on the other side of a large room and you can probably read farther down that chart with a 10X, and maybe even with an 8 or 7X, because of this blurring effect.

The unfortunate truth is this: Mankind has accomplished a lot but we can’t change the fundamental realities of optics. We can, for example, dispense fresh, tasty cupcakes to people from ATM-like machines, but we can’t turn those same people into stable platforms for high-magnification optical viewing devices once they’ve finished their cupcakes. Or ever.

Because. They. Breathe.

Sure, you can mount a 12X on a tripod, but if you’re going to mount an optical instrument on a tripod and then lug it around, you may as well get an even higher magnification spotting scope—not only will it be a much more fulfilling experience, but it’ll look way cool and increase the tripod’s ROI.

Fact is, the very existence of 12X and, god help us all, 15X, binoculars have almost certainly hurt the sales and widespread adoption of binoculars by the general public. The common misconception that “more is better” when it comes to magnification often leads the “unfledged” optics consumer to purchase a glass with too high a magnification for her/his experience level and intended use. 

The result? An unsatisfactory or unpleasant viewing experience—completely devoid of the fun and Wow! factor that a quality full-sized 7X or 8X routinely delivers to its users. 

Which often means one less regular binocular user, one less potential birder, and one less future high-end binocular customer. Oh, and one more spurned plaything gathering dust in a closet.

I’ll make this simple (that’s what I’m here for): For your first and/or primary binocular, stick with 7’s or 8’s, and run away, run far away, from 12’s and anyone who suggests that you buy one. And you can thank me when you see me.

Now, about those “50’s”….

Should I Consider Buying A 7-power Binocular?

Why yes, yes you should. You have my permission to ignore all the people who tell you otherwise.

I LOVE my Zeiss 7 X 42 Classic (no longer manufactured, unfortunately) because of its stunning brightness and ultra-wide field of view (FOV is discussed elsewhere on this site)—look through this binocular and the “widescreen” image just “pops” out at you (if you’re not sure what “pop” means in this context, find one and try it!). Whenever I showed this or any other quality 7 X 42 binoculars to a customer (which I always tried to do regardless of what price range they said they were interested in) I’d always hear some version of “Wow!” or “OMG!” at the very first look. I even sold a few to some folks who were looking is a much lower price range—such was the power of that “Wow!” Factor.

But despite this Wow! Factor a 7-power not often an easy sell because people come to the buying process having convinced themselves, or having been told by an “expert” friend, that they need higher magnification (mostly they don’t, at least for their first or primary binocular). Let me illustrate.

Let’s say you’re looking at…oh I don’t know, the secretive and elusive Sasquatch, that’s 100 feet from you (hope you have a camera too!) Since a 10X binoculars makes things looks 10 times closer than they actually are, a 10X binocular will cause the Sasquatch that’s 100 feet away look like it’s 10 feet away. Similarly an 8X will make that same large hairy ape-like creature appear about 12.5 feet away, and for a 7X it will seem about 14 feet away. So…how noticeable is the difference between 12.5 and 14 feet away when you’re looking at a Sasquatch that’s 100 feet away? Well for me the answer would be “not much,” and with a 7X the Sasquatch will seem brighter PLUS with the wider FOV that a lower magnification provides you’ll see more area around the Sasquatch—meaning you’ll get a better look at what it’s actually doing (very useful when you’re dealing with secretive creatures) and it’ll be easier to follow it with your bins as it moves.

Now admittedly a Sasquatch is larger than many of the things you’ll be watching with binoculars, so yes, there will be instances where the perceived difference of 1.5 feet (to continue the example) might come in handy—but for my money the perpetual wider field and brighter image trumps the occasional slightly greater detail that higher magnification provides.

So considering all of these benefits and the Wow! Factor they produce, why then is the 7x is a vanishing breed?

As mentioned previously there is an almost inherent bias against 7’s as being “not enough magnification,” and this bias is self-perpetuating—people are told or otherwise get the idea that 7’s are “not enough power” so they don’t buy them; less sales mean optics manufacturers have a solid business reason to stop producing them (in fact, among the three high-end optics manufacturers only one—Leica—still makes a 7 X 42. It’s a wonderful glass.)

But the best way to sell a 7X is to put one in the hands of a customer, and watch the “Wow!” happen—but unfortunately there are decreasing opportunities to do this with the rapid decline of brick and mortar optics stores with knowledgeable sales help. So while the online stores offer the convenience of at-home shopping, they are contributing, if only indirectly, to the disappearing 7 X 42 binocular—the best-kept secret in nature optics.

So when you’re shopping for a binocular, do yourself a favor and at least try to get your hands on a 7 X 42 (I’ll be happy to show you mine when we meet).

Your eyes will thank you.

The Basement Binocular

I sold binoculars and spotting scopes for 15 years at a nature store on a wildlife sanctuary in NJ. I sold them to birders primarily, but also to hikers, kayakers, sporting event enthusiasts and to people “gearing up” to go on cruises or adventure tours like safaris, and who were told by their tour companies to purchase a pair of binoculars for the full enjoyment of the trip.

The law of averages suggests I also sold a few to peeping toms, but since they don’t self-identify as such I have no independent confirmation of that.

For those people who were current and regular optics users the sales process was fairly simple, owing to their familiarity with optics and what they needed and wanted. Most of them were trading up from inexpensive bins; many buying their “dream” binocular that they had saved for and lusted after for many years. It was a singular delight to help them attain their long sought-after “Holy Grail” optic.

But a majority of people I helped were buying their first “real” binocular (or spotting scope) and for those people the process was more challenging but equally rewarding. Often they knew little if anything about optics beyond the fact that they’re designed to magnify whatever you were looking at, and they are…(and these were common misconceptions) heavy and hard to hold, difficult to look through, and generally not a lot of fun to use.

Wait, what? Heavy, difficult, not fun? Are we talking about the same thing here? Why were these negative myths surrounding binoculars so common?

I blame the “Basement Binocular.”

From my experience, almost everyone has a Basement Binocular. It’s that old binocular, often of World War II vintage (or looking like it), that was stored in the basement (or attic), handed down from a family member now gone: “I think he/she watched birds. He/she was always considered the crazy one in the family.” It was heavy, dirty, and smelled a little funky (that’s known as “old optics smell”).

But worse than the shabby outward appearance and unfortunate aroma, in most cases Basement Binoculars simply don’t work or at best don’t work very well—and being unfamiliar with optics and their capabilities there’s no way for the inheritors of these ancient instruments to know this. 

The result? Generations of people form their opinions about binoculars based on Basement Binoculars that bear little resemblance to the light, bright, relatively inexpensive and yes, odor-free, optics available today. Which means there are an awful lot of people unknowingly depriving themselves of the simple joy of using binoculars to watch birds in their backyards, or better yet, to enrich the experience of everything they do outdoors.

I’ve seen my fair share of Basement Binoculars, brought to me by folks seeking an evaluation before they even consider purchasing a newer, more modern pair. So I know first-hand that many of these people are completely unaware of how inferior these old binoculars are, and consequently are pleasantly surprised at the optical quality, weight and price of newer models. If only everyone stuck with a Basement Binocular would just…

Wait, that’s it! That’s our mission, then. All of us with modern optics have to do our part to eliminate the Scourge of the Basement Binocular!

Show off your optics!

Whether you’re reading this in preparation of buying your own first good binocular (thank you!), or if you who already own good optics but may be saving for your “dream” pair—share your optics with friends and family who are not current users. You never know how many of them are missing out on the pleasures of nature optics because of a mistaken impression they’ve received from a vastly inferior binocular hanging out in their basement (I’ve seen it happen, many times).

No I’m not going to ask you to go rummaging around a dark, dank basement of a neighbor or family member who’s currently not enjoying the pleasures of using a binocular. I would never ask that.

Then again, I’m not going to stop you either.

How Much Should I Spend?

Q: How much should I spend on my binocular?
A: You don’t have to spend a lot of money to get a perfectly decent binocular.

When I started selling binoculars back in 1997 you really couldn’t confidently make this claim. 

There have always been inexpensive binoculars (thank you, Hasbro and Sears Roebuck & Co, among others) but it would be a stretch, to say the least, to label them “perfectly decent” by today’s standards. Granted, that’s a highly subjective descriptive phrase, but it’s doubtful that anyone would argue the point that at any given price today’s binoculars are brighter, sharper and often weigh less than the Optics of Yesteryear. 

For this we have birders to thank.

The ever-increasing army of birders rely on their binoculars to pursue their passion, depending on their trusty instruments to help them identify birds, often by anatomical feature or field mark, under a host of weather and light conditions. To pass muster with birders and their frequent, often daily, use, optics need to be bright, rugged, dependable, portable and weatherproof. Clearly birders demand more from optics than other user groups and the market has responded with quality and feature enhancements that benefit everyone. And the shift of optics manufacturing to China of all but the highest-end binoculars (German and Austrian-made) led to another universal benefit we all love—the decline in price.

Today there are binoculars costing $300 that have the same optical quality and features as ones costing three times that or more just a couple of decades ago. You can even find some bins in the $100-$200 range that have a lot going for them and any one of them would make an excellent choice for first-time or young person’s binoculars. Their relative quality and ease of use will likely convert you into a regular binocular user but there’s a downside—chances are these less expensive optics won’t last a lifetime. Fear not: with frequent use you’ll soon become a more discerning optics consumer and, if you’re like most people, start longing for a better (and more expensive) pair. 

In other words, you’ll be hooked.

So how much should you spend? Obviously it depends on your budget, but if you can swing it I would recommend putting aside at least $300 for that optics purchase. At that price you can pretty much guarantee not only a great view but also something that’ll last until you’re ready for the big leagues—optically speaking. 

$300 buys a lot more binocular than it did when I started selling optics in the 1990’s.

Can’t swing $300 right now? No worries: these days less than that will nab you a fine instrument, fully capable of giving you a bright, sharp image under all but the most challenging of light conditions—a perfectly acceptable stepping stone to your dream high-end binocular.

The Optics Formula: An Introduction

What by What?
The “Optics Formula”: An Introduction
Why Those Two Numbers With An “X” In The Middle Are Such A Big Deal
(Magnification by Diameter of the Objective Lens (the end away from your eyes)

Every binocular has this handy “mathematical formula” attached to it (and usually printed right on the binocular). It tells you an essential “story” about that binocular—but not the whole story. The good news is that knowing what the numbers represent allows you to eliminate a huge number of available optics from your purchase decision, making the buying process easier and less confusing.

The first, or left number is the magnification, or power, of the binocular (8X = 8 power). Simply stated an 8 power binocular makes the object you’re looking at appear 8 times closer than it does with the naked eye. Since presumably you’re using the binocular to get a closer look, this number is key, but as is true so often in life, bigger doesn’t necessarily mean better. 

True, with a higher power binocular you are magnifying to a greater degree your target image, but you’re also magnifying any movement of the holding platform of the device—meaning you. So with an 8-power binocular you are also magnifying the image-distorting effect of such things as hand tremor (which everyone has whether they know it or not) and the beating of your heart (which I assume you have as well). So the target image is larger, but the quality of that image in terms of detail you can discern changes little, if at all.

Higher magnification also narrows the field of view (discussed elsewhere on this site) and decreases brightness, thus further limiting its advantages. It’s for these reasons that I strongly advise limiting the magnification to 8-power with your first or primary binocular (see “Optics Formula, Rule 1).

The second, or right, number is the diameter in millimeters (metric system alert!) of the objective lens, which is at the opposite end of the barrels from the ends to which you’re putting up your eyes. Since this is where the light enters the binoculars before traveling through the barrels and exiting the other side (the ocular lens), this is a jumping-off point to how bright the image will be—but it is by no means the only determining factor (I explore brightness factors in another post). As with magnification, bigger isn’t always better, but it’s often heavier, owing to the dense, heavy optical glass down at that end. And that, more often than not, is a really big deal—see “The Most Important Binocular Spec” elsewhere on this site.

For arithmetic aficionados there’s a measure of brightness called “exit pupil,” expressed in millimeters, that can be calculated by dividing the magnification into the objective lens diameter: for a 7 X 42 the exit pupil would be 6 mm; an 8 X 32 optic would have an exit pupil of 4mm (and if you’re like me, to figure out the EP of a 8.5 X 42 you’ll need a calculator). Or just skip the math, hold the binocular up to a light source and look at the ocular (eyepiece) lenses; that light round dot in the middle of each ocular lens is the exit pupil, and now you can figure out its diameter! Better yet, stack an 8 X 32 on top of a 7 X 42 and look at the eyepieces—the round dots on the 7X (6mm) are noticeably larger than those on the 8X (4mm). That’s the column of light hitting your eyes—a vivid demonstration of how much brighter the 7 X 42 is! Congratulate yourself, you’ve just done both Science and Math!

You’ll see binocular magnifications (first number) as low as 6x (3 or 4x if you’re looking at opera glasses) and as high as 15x (more if they’re tripod-mounted). You’ll see objective lens diameters as low as 20 (compact or pocket binoculars) and as high as 56 (otherwise known as too-heavy-for-humans-to-use binoculars). That gives you a lot of potential (magnification) X (objective lens diameter) combinations to sift through when you’re deciding on a binocular, but good news! I help you eliminate a ton of them in the following posts on the Three Optics Formula Rules.

Optics Formula, Rule 1:

“If the first number in the optics formula (“8 X 42,” for example) is higher than 8, DON’T BUY IT.”

I’ll probably catch some hell for this one (and for at least some of the others) but do not buy a binocular stronger than 8 power—that is, if you want one that will give you the best image possible, be fun to use, and be something that you’ll continue to use down the road.

Above 8 power all the downsides of higher magnification start becoming more prominent, slowly eating away at the quality of your viewing experience and the likelihood you’ll keep bringing them along when you go out.

Generally speaking, with higher magnification binoculars the field of view will be narrower, the depth of field will be shallower, the image will be less bright (brightness goes down when power goes up) and less sharp (increasing the magnification of your hand tremor increases the subtle blurring of the image).

Obviously these statements are broad generalizations but their essential truth can be easily demonstrated by comparing 8 and 10 power binoculars with the same objective lens diameter (second number of the formula) by the same manufacturer—so everything is identical except for the magnification.

I’ve personally done this test many times, but more importantly I’ve encouraged countless customers who came to me saying they wanted a 10 power binocular to do the same test before they purchased (actually I kind of insisted on it).

I was blessed to have sold nature optics on a wildlife sanctuary, so I was able to construct the perfect optics test protocol: Take an 8-power and walk a trail for a while, looking at birds, leaves, berries, whatever one encounters on the trail. Then take the 10-power on the same trail and do the same thing. Once you’ve tried both, I would say, you’re free to buy whichever one you want.

In practically every instance the customer bought…the 8-power. No surprise.

(With the decline in the number of brick-and-motor stores with optics-knowledgeable staff, and the increasing popularity of online optics stores, in-person product demos and side-by-side comparisons like the one I just described are becoming, sadly, a thing of the past. Some online nature optics emporiums do go out of their way to help you, backing that up with liberal exchange/return policies—but there’s just is no substitute for hands-on tryouts for binoculars.)

Does all this mean that I dislike 10 power binoculars? No, I dislike 12 power binoculars, as well as the Voldermort of optics, the dreaded “15 power.” Yes, there’s a place for 10 power binoculars—that place is a hawkwatch platform like the Montclair Hawk Watch in Montclair NJ, or any of the other many hawk watch locations in the US and elsewhere. In fact a 10 power is often preferable whenever and wherever you’re looking at birds (or anything else) at long distances. Over the years when a few people have told me that ALL they do is watch hawks seasonally—a singular use for a versatile instrument I simply don’t understand---I just told them to go ahead and buy the 10X. 

Another instance where you can justify the purchase of a 10X is if you are one of those people who are fortunate to be able to afford multiple binoculars, in which case a 10 power makes a perfectly acceptable second binocular.

So again, a 10X DOES have its place, but for your first or primary binocular, a 7X or 8X is the way to go. You don’t need a specialized glass for long-distance viewing, you want one that’s versatile, which is to say one that works well in all of the situations in which you would want a closer look.

And that’s every time you go outside, right?

Optics Formula, Rule 2:

If the second number of the “optics formula” is higher than “45,” DON’T BUY IT.

Uh-oh, I think I’m in trouble again.

To review, the second number is the diameter of objective lens, or the end opposite the end in which you’re looking, expressed in millimeters.  It’s the jumping-off point to how bright the binocular will be, so once again there’s a tendency to think “bigger is better” and “more light in, more light out.”

Um, yes and no.

A lot happens to that light as it journeys from its objective lens entry point, through the barrels, out the ocular lens (the eyepieces) and into your eyes, so the “more in, more out” concept is even more of an over-simplification than…well, all the other optics over-simplifications.

True, you want the brightest image possible, but yet again we find ourselves asking the question “but Mr. Science (that’s me in this scenario), at what cost?” For example, a 100 mm objective lens would give you a ton of light-gathering power, but you’d have to roll it around in a little red optics wagon to go from place to place—and that wagon’s not included with the binocular.

So the cost of a larger, greater light-gathering objective lens that would give you that brighter image is…

Weight.

When you increase the size of the objective lenses on the non-eyepiece ends of the barrels of your binocular, you are by definition increasing the amount of glass in those ends—and that’s not just any glass, that’s dense, heavy optical glass—well, that’s assuming it’s not made by Hasbro.

I talk more about weight elsewhere, but for now just know that there is almost always a trade-off between weight and brightness, and that, trust me, you’re better off if you let weight win—in most cases, choose the lighter, slightly-less bright binocular and I guarantee you that you won’t regret it.

Ask yourself: which is brighter: the less-heavy binocular that you take with you, or the greater light-gathering but heavier one you leave in the car because you don’t want to carry that “thing” around?

As with anything else, there are exceptions to the “nothing over 45” rule. If you’re a woman or man with good arm and upper body strength and/or large hands you may feel more comfortable holding on to a larger binocular—you may even feel that an optic with some “heft” to it helps you keep it steady as you hold it up to your eyes. If this describes you than by all means try out some bigger 50mm binoculars. But bear in mind the following rule which, despite the fact that it defies all laws of physics, is an accepted truth among birders and other binocular users:

“A binocular is heavier at the end of the day than it is at the beginning.”

If you can explain the physics behind that, please contact me.

Optics Formula, Rule 3:

If the second number is lower than “30”—DON’T BUY IT.

The second number of the “Optics Formula” is the diameter, in millimeters, of the lenses in the ends of the binocular away from your eyes—the objective lenses. Below 30 mm in diameter and the binocular is considered a “compact” or “pocket” binocular.

So I’m telling you to eliminate from consideration all small compact or pocket binoculars?

Yes, for your first or primary binocular that’s exactly what I’m telling you.

That’s when you want a full-sized binocular. You want a good, clear, bright, sharp image under most light conditions when you’re first making your way in the optics world. You want something you can grip with both hands as you steady it while holding it up to your eyes or eyeglasses, and you want to be able to do that quickly before whatever it is that you want a closer look at takes wing or otherwise heads for the hills.

You want something with some heft when you hold it up and proudly say, “This is my new binocular.” (“Heft” is a too-often ignored optical term.)

Owing to its size a compact binocular doesn’t let in a lot of light at the objective lens, so less light will strike your eyes—giving you a less-bright image that may work for sunny days but not for those times and situations of compromised light conditions—thereby restricting when and where you’ll be able to use it. Dusk? Forget about it. Severely overcast days? Probably not. Rainforest canopy? Well, see that woman to your right? She has a 7 X 42—borrow that (and I’ll bet you buy one when you get home…that is, if you can find one!)

Also because of their small size, in many cases compacts will be harder to use and you won’t be able to grasp them firmly with both hands, leading most to adopt a “teacup”-style grip that will make it harder to hold them steady when held to the eyes, thus leading to quicker hand and arm fatigue.

For all these reasons compacts have a poor reputation among serious binocular users. Years ago I bought a compact specifically for desert hiking—an awesome Leica 8 X 25—which I proudly showed off to my supervisor at the time, arguably one of New Jersey’s best and most well-known birders. He took one glance at the small optic in my hands and blurted out, “why would anyone buy that binocular?” Yes, that looks cruel on the page (and admittedly it did bother me at the time since I had paid a fair amount for it) but it merely illustrates the degree to which good birders count on a bright image for bird viewing and identification, and for them the light provided by compacts is simply not up to the task.

But despite this conventional wisdom and the aforementioned downsides, a compact binocular does have its place—but as an additional binocular for specialized uses like hiking, kayaking, and any travel where there’s stringent restrictions on luggage weight. In those and other instances it’s clearly better to have something rather than nothing at all—and where the purchaser is well aware of the compact binocular’s many downsides before laying down his or her money.

One final point about these small binoculars, one that is a particular pet peeve of mine. Walk into many stores that sell nature optics and ask for a “children’s binocular” and more often than not the untrained salesperson (or even a trained one looking for a quick, easy sale) will suggest a compact binocular—you know, a small binocular for a small human being?

No. No. No. As difficult as it often is for an adult to use a compact, it’s usually way worse for kids. Even though their hands are smaller, a compact binocular is almost always a highly inappropriate choice for children. Leave (or hang up on) any store making that recommendation.

Besides, several optics manufacturers make a perfect binocular for kids—and that’s discussed elsewhere on this site.

Uncle Ned's Bins

Uncle Ned may be the best birder you know, but his binocular is probably not the best binocular for you.

Sure, old Neddy knows a ton about birds, and he’s been your birding mentor since you got hooked after seeing your first Indigo Bunting. And gosh darnit, that view through his bins is nothing short of spectacular. But before you go out to buy the identical binocular (that is, if you can afford it) consider this: just because you get an awesome view with your occasional brief look through Ned’s bins doesn’t necessarily mean it’s the ideal one for you. The “perfect” binocular for YOU will need to fit your hands, your eyes, your use and your budget—so unless you’re Ned’s clone it’s likely to be a different binocular whispering in your ear when you’re ready to pull the trigger.

Think of it like buying a pair of eyeglasses—you see all the different styles that people are “wearing,” but in the end it’s an intensely personal decision, based not only on how you intend to use it and how much you have to spend, but also on the size of your hands, the distance between your eyes, how much weight you can comfortably hold in your hands and deal with around your neck—and yes, whether you wear eyeglasses or not!

Sure, go ahead and get all the recommendations and advice from current binocular owners you want—getting different perspectives on an assortment of optics as you information-gather prior to your purchase will be indispensable. Most owners are strong advocates for what they’re using and will be happy to help you with your research—unless they’re in that optics limbo between “good enough” and “dream binocular,” in which case they’ll bend your ear with why you should buy what they’re saving to buy.

Unfortunately, despite their best intentions you’re probably better off ignoring them. What about all the optics information and advice on the web? I would say: proceed with caution. Yes, there’s boatloads of it, and while much of it is accurate and helpful, there’s plenty that’s just plain wrong (especially in comments on blogs and elsewhere). The websites of optics manufacturers will, of course, accurately portray their products (in the best possible light, of course) and provide you with the individual specs you will need to make your purchase decisions. The web-based optics stores will have the specs too, as well as so much how-to- buy and product information that your head will spin, and since they carry practically everything in order to cater to every potential type of customer and use, it’s difficult to wade through the information onslaught to find exactly what you need.

And because they carry just about everything, most of what they have won’t be appropriate for your intended use. For example, all of the online optics emporiums carry 12 (magnification or power) X 50 (size of the ends away from your eyes) binoculars, but 12 X 50’s are unsuitable for bird watching and most other nature activities—a questionable combination of power and size that is just shy of useless for most mere mortals (perhaps if Superman didn’t already have super vision…)

So, just like Uncle Ned’s bins, most of what an optics store carries—whether it’s brick &
mortar or online—will not be a good fit for you and thus not give you the many hours of
viewing pleasure that would transform you into an Uncle Ned-like long-term dedicated optics user. The only way to get there is to do your homework (including quality time on the Pop Optics site!) speak to the pros (like Pop Optics’ Denis Cleary!), and when you can, do your hands-on tryouts. There’s no better way to find your ideal binocular!

Using Binoculars With Eyeglasses

“I have to take my glasses off to look through a binocular, right?” (I’ve lost track of how many times I’ve been asked this).
No. No you don’t.

In fact contrary to what you may have heard leaving your eyeglasses on when looking
through a binocular can give you a benefit non-wearers don’t have. So there—a rare
win for us “four-eyes.”

If you spend any time with other folks using binoculars (and I would certainly
recommend that you do) you’ll likely see this familiar scene: people wearing eyeglasses
are among a group of birders walking around with binoculars in their hands or hanging
around their necks, and…wait! What just flew into that tree? The eyeglass-wearers flip
their glasses on top of their heads, then look through their binoculars into the tree
(usually, hopefully, the eyeglasses don’t fall backwards off their heads).

Oh well, whatever it was we lost it.
Put the binoculars down and the glasses back on.

Me, I’m a lazy eyeglass-wearer, and I simply don’t want to do all that every time I use
my binocular. Not to mention that it’s unnecessary and often counter-productive.
Sure, we eyeglass-wearers may have to work harder at the outset to get the right “fit,”
paying special attention to the eyecups and a spec called eye relief (more about that
later) but it’s time well spent. And for most people you only have to do it once.

First, the eyecups: on all modern binoculars the eyecups adjust to accommodate the
viewing needs of eyeglass wearers. The rapidly-disappearing, older-style soft rubber
eyecups fold down for eyeglass use; the newer-style hard rubber-type twist down
(usually by rotating in a clockwise direction). The reason the eyecups need to be
adjusted is simple and brings us to the concept of “eye relief.”

Eye relief is the distance from the ocular lens (the glass at the smaller end of the
binocular, the end you look into), expressed in millimeters, that the eyes need to be to
see the full image with full field of view. If your eyes are beyond that distance you’ll only
get a partial view, giving you the “looking through a keyhole” experience.

So imagine that the eyecups of your binocular are in the default, “up” position. If you
look through the binocular without wearing glasses your eyes will be resting comfortably
on the outer edge of the eyecup, the depth of which puts your eyes (more or less) at the
ideal position for seeing the full view that nature (or rather, the manufacturer) intended
for that binocular, enjoying full field of view.

But look through the binocular in the same “up” position while wearing glasses and your
eyes are no longer in that optimal position—that’s where your eyeglass lenses are. Your
eyes are some distance away from that preferred position, and depending on a number of factors—how deep set your eyes are, the thickness and curvature of your eyeglass
lenses, among them—you’ll only see a portion of the image, making it more difficult to
focus on what you want to look at, and in the case of living things like birds, more
difficult to track movement.

Now with your eyeglasses still on, roll or twist down the eyecups, and rest the ocular
lenses gently against the surface of your eyeglasses. Assuming that the binocular offers
enough eye relief distance your eyes will now be in approximately the right position to
enjoy the same full image as non-eyeglass wearers. Plus the ability to gently rest the
ocular lenses against your eyeglass lenses allows you to stabilize the image (reducing
the “shake” from hand tremor) and also helps to diminish the hand and arm fatigue that
can happen when holding the binocular for long periods of time.

So there you have it—actual benefits of using a binocular with eyeglasses! Time to get that eye exam you’ve been putting off!

Most people who wear eyeglasses should enjoy a fantastic viewing experience with the
eyecups in the full “down” position (either rolled or twisted down). For some, however,
there will still be problems—most often an annoying dark “shadowing” effect around the
edges of the field of view. The fancy-schmancy term for this is “vingnetting,” but
whatever you call it it’s often caused by too much eye relief for the user, and very likely
a major reason why many eyeglass wearers ditch their glasses when using a binocular.
All is not lost, however. The twist eyecups on most modern binoculars can adjust, “click-
stopping” in several positions from fully-up to fully-down. So depending upon the
characteristics of your eyes and glasses you may enjoy a better viewing experience by
twisting up the eyecups to first “click-stop” position.

Yet another reason why it’s ALWAYS better to purchase your binocular in-person from a
knowledgeable optics salesperson rather than online. You should know that if you wear
eyeglasses there will be some binoculars on the market that WILL NOT work for you
and your glasses regardless of what you do. So once again having an optics expert with
you when you fit your new binocular to your eyes, glasses and hands will ensure a
lifetime of enjoyable use…or at least, long enough for you to trade up to your dream binoculars.