Leica’s Duovid 8+12x42

Variable-power riflescopes have dominated the market for 30 years now, along with variable spotting scopes. So why are variable binoculars almost unknown? They do exist, but only in relatively inexpensive models, which have not found favor among serious hunters - until now.

Until now, serious hunters have been forced to pick between magnifications. Usually the choice comes down to 8x or 10x. Most hunters choose 10x, because they think they’ll see “better” with more magnification. To a certain extent this is true, but with 8x the spot called the macula lutea in the rear of your eyeball that perceives detail is effectively over 50 percent larger. So while 10x is undeniably better for counting the tines on a buck’s antlers, 8x works better for finding the buck in the first place.

Far-gone open country hunters often use even more than 10x. When the country’s really wide and the quarry difficult to see, I often carry my Leica 12x50, because it provides a definite advantage over even the best 10x glass. But it’s heavy as pig iron and slow to use on nearby game, both because of its narrower field, and because higher magnification means that at shorter ranges, it must be refocused every time I look at something else. This isn’t necessary with 8x binoculars.

Some hunters use even more magnification, particularly 15x. But unless they mount a 15x glass on a tripod, they’re kidding themselves. Most humans simply cannot hand-hold 15x binoculars steadily enough to see more detail than they could through 12x. Sure, the image is bigger, but the tiny tremors inherent in the human hand will fuzz important detail.

This problem grows even worse with inexpensive “zoom” binoculars, because when turned up to 12x or 15x, they aren’t particularly sharp in the first place. Add some hand tremor, and deer antlers don’t stand out any better than through a truly good 10x glass.

Until now, the only serious solution was to carry a smaller glass for finding game (particularly at under half a mile) and a big honker for perceiving detail. I often did this, packing an 8x32 or 8x42 for general glassing and the pig-iron 12x50 for gazing across grand canyons. The big binocular rode in my day pack, where it often crushed my lunch. Not only was this system expensive but annoying to anybody who prefers their PB&Js with some loft.

Now we have Leica’s solution that, at just under $1,500 suggested retail isn’t exactly inexpensive, but beats the heck out of a $750 8x and a $1,300 12x, my previous solution. And at 34 ounces, it’s also only a little over half the weight of my two-binocular “system.”

Calling the Duovid 8+12x42 binocular a “variable” will get me in deep moose manure with my hunting buddies at Leica. Please note the “+” symbol between 8 and 12, which means that it’s both an 8x and a 12x glass, not an 8-12x “zoom.” For the moment let’s call it a “dual-power” glass, as Leica does, then modify that statement later.

There haven’t been many high-grade “multiple-magnification” binoculars before because of some inherent problems. Variable rifle and spotting scopes are relatively easy to make, since they’re both single telescopes, but binoculars are two telescopes. Both “barrels” must focus at once, which became even more of a problem in the past decade as waterproof optics became all the rage.

The more moving parts in any optical system, the more difficult it becomes to seal against moisture. Add multiple-magnification to a focus system and it’s tough to really seal any binocular. Leica got around the problem by putting the power-change into each eyepiece. Instead of turning a single ring to change magnification, as you do in variable scopes or cheap zoom binoculars, each eyepiece needs to be turned individually from 8x to 12x. This takes, oh, three to four seconds.

A lot of previous multiple-magnification binoculars also suffered from too wide a power range. While 3-10x performs many useful tasks in a riflescope and 15-40x works great in a variable, there’s no need for such a wide range in a binocular. Magnification under 8x can be useful, but nobody will buy it anymore, and anything above 12x runs into the hand-tremor problem noted above.

(While both Canon and Zeiss make binoculars with internal systems that dampen the effects of hand tremor, either adds some weight and bulk. Canon gets around this by making the objective lenses smaller, since objective lenses are the single biggest source of weight in most binoculars. I’ve tried these while hunting in Africa earlier this year, and the 32mm objectives in its 10x simply don’t provide enough light or detail for serious hunting. A high-grade Swarovski 10x42 allowed me to see a lot more detail, despite the Canon’s damping system. Zeiss’s system is even heavier and bulkier, the reason the only dampened binocular it has ever offered is its 4-pound 20x60, which costs just under $5,000.)

So Leica’s 8+12 offers the finest compromise available at the moment. The optics, as you might expect from Leica, are as fine as any made. Various Rifle staffers used the Duovid on hunts soon after the binocular hit the market earlier this year, and it worked great. For most glassing we left it on 8x, where the wide field of view and broader area of detail helped find game, whether brown bears or prairie dogs. If we spotted something not quite identifiable, we turned the eyepieces to 12x and could tell if that big brown object across the valley was a log or a bear or the small tan object across the draw was a prairie dog or a burrowing owl.

Oh, and they can be used between 8x and 12x. I tried it, briefly, by turning each eyepiece halfway between 8x and 12x. Presto, 10x! But why use 10x when you have 8x and 12x available? Which is probably why Leica didn’t put “clicks” on the eyepieces at 9x, 10x and 11x.