From time to time it is necessary to take a look at the larger optical picture — to review the current optical landscape and see how the land lies from a birding standpoint. Over the past few years the number of moderately priced roof prism binoculars, in particular, has burgeoned . . . and, to be honest, their introduction has changed the shape of the market significantly. Here then is the broad view of the current binocular landscape.
The ultimate birding binoculars, truly bird-worthy binoculars, would have a bird-in-the-hand-view (exceptional resolution, contrast, color fidelity, and brightness), excellent eye relief and field of view, good close focus, complete weatherproofing, and extreme durability, in a package that is easy to carry and hold steady for a full day in the field. Unfortunately the ultimate birding binoculars — with that full set of features, 100% of possible optical performance and 100% of field-worthiness — do not yet exist. Given the compromises that must be made to allow binoculars to be at least reasonably affordable, today's binoculars market falls out something like this:
Ultimate optical performance is provided by a single example of what can be done with the porro prism design. The Nikon Premier SE (formerly Superior E)
10x42 provides as close to a true bird-in-the-hand view as I
have yet seen. Handling is also exceptional. However, while durability should not
be an issue, it is not weatherproof in any way. Finally,
I wouldn't choose 10 power binoculars as my regular birding glass.
They are simply too difficult to hold steady over a full day in the
field. The Nikon has 100% of the optical performance currently
available, and 85% of the field-worthiness.
Next
come a set of high quality, cost-is-no-object, roof prism binoculars
that provide 99% of the optical performance that is currently
available, and 95% of the field-worthiness. These include full-sized,
water and fog proof, 7 to 10 power glasses from the Leica Ultravid line,
the Swarovski SLCs, the Bushnell (formerly Bausch & Lomb) Elites, and the Zeiss Victory FL series. Without direct
comparison to the Nikons, it would be very easy to believe that these
glasses provide as good a view as you could possibly get . . . hence the
99% bird-in-the-hand rating. All of them are slightly too heavy for a full day
in the field (though their mass makes them exceptionally steady in
the hands until fatigue sets in). They all require some sort of
exceptional support system — a wide neoprene strap, a binocular harness system,
etc. — or they will cause neck and shoulder pain by day's
end . . . hence the 95% field-worthiness rating.
In this same class are the mid-sized waterproof roofs from Swarovski, Leica, and Zeiss. Their balance of features shifts to something like 95% bird-in-the-hand and 99% field-worthiness. Close in and in uniform light their optical performance is every bit as good as their full-sized siblings. However, as distance increases, and as the lighting becomes a more complex mix of light and shade, front and back-lighting, the limitations of the smaller objectives become evident. In field-worthiness, though, they come close to being the ideal birding glasses. The Leica 8x32 is still my favorite all around birding glass.
From here, the field splits along prism design lines. On one hand you have a group of exceptional porro prism glasses, often specifically designed for birding, and on the other you have a growing group of moderately priced, waterproof and fog-proof roof prism binoculars.
The
porros: Swift Ultras and Audubons, the smaller Nikon Premier
SE, and glasses from
Bushnell are all in the $300 range and offer by far the best optical
value currently available — ranging from about 95 to 99% in
bird-in-the-hand value (and often covering that range in a single make and model due
to slight differences in individual units at this price point).
However, none of the porros offer the slightest weatherproofness and,
at this price point, durability is an issue. Not that they are
fragile. With care they should last a lifetime, but I would expect
any of them to require realignment and service at least occasionally
during that lifetime. Then too, the porro design makes for limited
close focus and generally slightly narrower fields than the best
roofs. You can find wide field designs, but the trade off is
generally reduced eye relief which cuts the field back to normal for
spectacle wearers anyway, and makes the glasses less comfortable for
anyone. Taken together with the extra bulk of the porro design, these
limitations give the $300 porros field-worthiness ratings in the
80-90% range.
On the other hand, the moderately priced roofs from Bushnell, Celestron, Leupold, and Swift (to limit it
to those I have tested so far) come in with bird-in-the-hand ratings of something like
85-90%, and field-worthiness ratings of 90-95%. In direct comparison with the
best roofs, or with the $300 porros above, all of these roofs show their limitations.
While the view is very good — eye relief is often excellent and close focus
is exceptional — in side by side comparisons, they all lack just a bit of
resolution and brightness. Are they good enough to be satisfying in the field?
Certainly. In fact, without direct comparisons it is hard to believe that anything
would give you a better view. Then too, their compact size, excellent body design,
and waterproofing (which also means dust-proofing) make them delightful to
carry afield. You might note that this assessment of moderately priced roof
prism binoculars represents a shift in my own attitude toward what makes for
bird-worthy binoculars. Over the past two years I have begun to give increasing
weight to weatherproofing in my assessments, and, as I have used roof prism
binoculars more extensively, I have come to understand more fully why many people
prefer the design to porros. Roofs have an inherent balance and elegance, a
feeling in the hand and at the eye, that porros just can't equal. It is easier,
today, for me to understand why someone would knowingly give up some optical
performance for the privilege of using roof prisms. Not that I would necessarily
do it myself . . . but . . . then again . . .
If you can't afford (or can't justify the cost of) the highticket roofs you will have to choose between birding-specific porros and the new crop of mid- and moderately-priced roofs. Ask yourself which is more important, a true bird-in-the-hand view or field-worthiness. If the view is your primary concern, go for the porros. If field-worthiness will get the glasses out into the field more often, go for the roofs. I have to say, that given $300-$350, and only $300-$350, to spend on binoculars right now, today, I would be hard pressed today make that choice myself. I can't honestly say which side I would come down on.
Finally, if you
are looking for a real bargain there are at least a few $100-150 porros
that make the bird-worthy standard. Of those that I have tested, the
Bushnell NatureView and the new Nikon Action series stand out. The
NatureViews are exceptionally well designed for birding
(with a bird-in-the-hand of 85% and field-worthiness of 80%). The Nikon Action series features aspheric technology to give amazingly good resolution and brightness (a bird-in-the-hand of
90% in the center of the field . . . though quickly going soft as you
approach the edges of the field). Field-worthiness is also in the 80%
range. I hope to do a budget test including these glasses in
the near future. It should be noted that there are few bargain roof
prism glasses to compare with the bargain porros, although that is changing as roof prism technology is becoming available at lower and lower price points as time goes on.
Revised 6/07