Wouldn't it be wonderful to own binoculars which weighed less than 12 ounces, fit in your pocket, and yet still provided a satisfying enough view of the bird to substitute for your full sized (or even mid-sized) binoculars, day-in-and-day-out? Wouldn't it be wonderful if you could fold your binoculars up and tuck them into the smallest corner of your purse, backpack, briefcase, computer bag—if they would go in the glove compartment of your compact car without taking out the owner's manual—if you could wear them unobtrusively wherever you went, like oversized jewelry, boardroom to ballroom, supermarket to sauna, biking around town or skiing down the slopes, so you were perpetually prepared for that vagrant Aztec Thrush?
Unfortunately, binoculars like that only exist in our dreams.
All compact binoculars are a compromise. For one thing, the laws of Physics are against them. The small objectives of compacts put a physical limit on both the resolution and brightness of the binoculars. Close in, in good light, that is not much of a problem, but as distances increase and light levels fall, compacts are always going to reach the limits of their usefulness far sooner than mid-sized and full-sized binoculars. Then too, really compact binoculars, the pocket-sized roof-prism models, are pushing the limits of what can be done with glass and metal. The precision tolerances required to make roofs work at all get even tighter as you shrink the dimensions, and mean that truly compact quality is always going to be very expensive. Finally, the small exit pupil of compacts makes them considerably harder to use than full sized binoculars. You have to place them much more carefully in front of the eyes and there is never that sense of ease of view that the best full-sized binoculars provide.
So, then, why would a birder even be interested in compacts? Well, of course, for all the "dream" reasons above. Compacts are go-anywhere, ready anytime, binoculars. There are times when even those of us who own the best full-sized and mid-sized binoculars would be well served, perhaps even better served, by compacts. During the months of this test of compacts, at least one pair found their way into my school bag every day. They went with me in my computer case to out-of-town workshops. They came with my Bible to church. They accompanied me on neighborhood walks with the wife and dog. They hung around my neck on a walking tour of the Freedom Trail and Quincy Market in Boston with 87 9th and 10th grade students. (I will even admit to having carried them to the balcony of a classical violin concert, where they allowed us to see every nuance of bowing and fingering and every flaw in the performer's make-up.) In every case, I knew that my trusty 8x32 Superior Es, or any of the full sized binoculars I have laying around the house, would have provided a better, more reliable, view of any birds I might see, but, the fact is, I would not have carried the larger glasses. The best binoculars are the ones you have with you when you see the bird. Then too, I had gained enough confidence in the compacts to know that, in all but the most extreme situations, they would show me the birds. And it is, as always, about the birds, not the optics.
I say, "I had gained confidence" because, in my last test of expensive, pocket-sized roof-prism compacts I did not find a pair that was satisfying enough to justify the cost. Things have changed. There are even two relatively inexpensive "semi-pocket sized" roofs in this test that would make good emergency binoculars for the traveling birder.
8x Roof-prism Compacts
What we have are two new truly pocket-sized compacts, an 8x20 and a 10x25, in the high-end Venturer line from Nikon, two new pockets in Zeiss's Victory series in the same sizes, and a set of semi-pocket roofs, 8x25 and 10x25, from Celestron's Regal and Leupold's WindRiver lines. The Celestrons and WindRivers are apparently "siblings under the skin." They appear to be optically and mechanically identical, distinguished only by differing body armors.
10x Roof-prism Compacts
Little Pockets, Big Wallets
I have to say right away that the quality of both the Nikon or Zeiss 8x20s amazed me. These are truly no-compromise pocket-sized glasses. Fully waterproof, phase coated, tiny, satisfyingly bright, with a relatively wide field of view, and delivering enough detail to the eye to make them useful in almost any birding situation. Close in, even in relatively dim light, they are easily the equal of their larger siblings. Only at distances of 50 yards or so do they begin to show their limits, and even then, only in direct comparison to larger glasses. The Nikons are a shade brighter. The Zeisses appear to have higher contrast and a perhaps a shade more resolution (at least in the samples I had).
Physically, both Nikons and Zeisses are about as small as you can get. They fold up quite differently. Zeiss turned their industrial designers loose on these. The Zeiss glasses have only one hinge, near one tube and fold in so that the hinged tube nestles under the focusing bridge. The Nikons are more conventional, hinging in from both directions. It doesn't make a significant difference in the overall size of the package when folded, but the Zeiss glasses certainly have that certain something that sets them apart. The Zeisses are also a few ounces lighter. Both glasses look and feel like precision products, triumphs of both design and implementation: practical jewelry for the birder.
Nikon and Zeiss also took direct opposite approaches to focus and diopter adjustment. The Zeisses have the focus close to your eyes (the normal position for binoculars) and the diopter adjustment on the other end of the hinge. Because of the single offset hinge on the Zeiss glasses, the focus is also offset, but it falls nicely under a right hand first finger. Left handed birders beware. Nikon has put the focus on the far end of the hinge, away from the eyes and face, so it falls under your little fingers. Some may find this awkward, but it has the advantage when wearing a hat. You can focus without knocking the brim back. The diopter adjustment is on the eye-end of the hinge.
Finally, Nikon has maintained the excellent screw-in, screw-out eyecups featured in the rest of the Venturer line in their compacts, while Zeiss has settled for pop-up, pop-down cups. (see photo below.) Good for Nikon, bah on Zeiss!
I would be completely satisfied with either of these pocket-sized wonders. They come really close to being those dream binoculars we were talking about earlier. In fact, while carrying either of these glasses I would be confident that nothing, no vagrant, no subtle pleasure of a familiar bird's plumage, was going to get by me. They provide a view of the bird that can only be bettered by carrying considerably larger binoculars, and literally fit in most pockets.
And what about their 10x siblings? Both the Nikon and Zeiss 10x glasses are enough bigger so that they stretch the limits of the "pocket-sized" definition. They would easily fit in a jacket pocket, or the pocket of a birding vest, but not much else. As you would expect in 10x glasses, their fields of view are considerably more narrow, at around 5° (263 ft. at 1000 yds.), and the additional power, while it can provide extra detail at distance, does not, in my opinion warrant the extra difficulty of use that the 10x glasses entail. Still, if you are stuck on 10 power, these have the same quality and features as the 8x Venturer and Victory compacts, and I would not hesitate to recommend them to any birder.
Of course, while these may be dream quality binoculars that will fit in most pockets, they might not fit equally as well in most wallets. Quality and compactness of this caliber do not come cheap. List prices are in the $500 range, and street prices between $350 and $400.
Big Pockets: Little Medium-sized Wallets
Which brings us to the second set of compacts in this test. The Celestron Regals and the Leupold WindRivers are both waterproof, phase-coated, roof-prism compacts, with street prices in the $200 range. They can not be said to be pocket-sized though, since they don't fold up tight enough to fit in any pocket short of a birding vest. Don't get me wrong: as you can see from the photos above they are still quite small—just not pocket-sized.
Both are good evidence of just how difficult it is to make a roof-prism compact with anything like the performance of a full-sized glass. While the 8x models yield acceptable brightness, they do so at the cost of a limited field of view (again around 5°). Then too, in direct comparison with the Nikons and Zeisses in this test, they simply did not have the crispness and detail of the more expensive glasses.
Physically both glasses are very nice. The Celestron has a somewhat "high tech" look with a sculpted armor that fits the hands well. Leupold went for a more functional look, which results in a slightly more compact package without the sculpting. Both feature pop-up, pop-down eyecups, but with "click-stops" that make them more functional than the Zeiss pop-ups. Either would be a satisfying emergency binocular, to tuck in your luggage while traveling, but neither would satisfy in day-in, day-out birding.
At 10x the differences between the expensive compacts and the next level become even more pronounced. I could not recommend either the Regal or the WindRiver 10x Compact to any serious birder.
One the Other Hand
(or "Big pockets, little wallets...")
Sharp-eyed readers (and we are mostly birders here, after all, so I expect all of you to be sharp-eyed), might have noticed the lone porro hanging off the bottom of the bunch of compacts in the lead photo.
I have always maintained that the best value and performance in compacts can be had in the relatively inexpensive porros. To test that assertion once more I dug out a pair of Swift, under $200, Trekker 8x26 porro compacts I had on hand and put them up against the expensive roofs in this test. The porros were, as expected, both brighter and sharper than any of the roofs, including the Nikon and Zeiss. In fact, the $200 Swifts were the only compacts that approached the performance of full-sized binoculars at distance. Not only that, they are waterproof. They do still have the those funky roll down rubber eyecups, and are not even as compact as the 10x Celestron and WindRiver roofs, but the optical performance can't be beat. And they are pretty small, not pocket-sized (unless, again, you are wearing a birding or photo vest), but certainly small enough for the purse, backpack, computer case, glove compartment, etc. At $200 you can't expect them to be as rugged as $400 roofs, but, with reasonable care, porro compacts can give years of service. I am not singling the Swift compacts out here, merely using them as an example: if you can live without the waterproofness, many of the porro compacts in the $70-$150 price range, including glasses from Nikon, Pentax, Bushnell, Celestron, WindRiver, and many others, are optically excellent. So if your main interest is in optical performance, and you are willing to exercise some extra care in weather and handling, you might just be able to save yourself a few hundred dollars, and still have compacts that come close to fulfilling every birder's dream.
Final Words
On the other hand, if you are into precision, ultimate compactness, absolute ruggedness, and the jewelry like experience of the best roofs, either the Nikon Venturers or the Zeiss Victorys should be on your shopping (or wish) list.