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If those models are above your
budget, check out the redesigned Nikon Monarch ATB 8x42 or 10x42 ($290
and $329, respectively; 21 oz). These binoculars are waterproof and fogproof
with phase-corrected roof prisms for high edge-to-edge sharpness. For
maximum light transmission, they feature a wide objective lens and exit
pupil plus lenses with full multi-coating. Both are also shockproof, thanks
to a durable metal-alloy housing while the rubber armor provides a firm
grip, wet or dry.
Wide Angle Design
While maximum magnification may be important for some uses, high-powered
binoculars have a very narrow field of view. Many outdoor and sports enthusiasts
prefer a model with a wider field of view, great for scanning a large
area or for following action subjects. Hence, we're seeing more
wide angle models, such as the new Minox 7x42 BR A.L.T. ($450; 785 g)
from Leica. Featuring a field of view of 403 ft at 1000 meters, the Minox
binoculars offer other benefits, including a large exit pupil (6mm) for
a bright view, aspherical elements for great edge sharpness, M* lens coating
to minimize reflections, and phase-corrected prisms for exceptionally
high light transmission. Like all Minox binoculars, this one boasts a
body of rubber-armored aluminum, high precision mechanical and optical
systems plus waterproofing and nitrogen filling to prevent internal fogging.
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Outdoor
photographers carry binoculars for scouting and observing
distant subjects, whether nature or sports. These days,
binoculars tend to be more versatile and include more convenience
features than ever before.
© 2003, Peter K. Burian, All Rights Reserved
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Close Focusing
Because binoculars are generally used for distant subject matter, few
models offer extremely close focusing (15-30 ft is common for 10x binoculars).
However, for certain subject matter such as butterflies and large birds,
you'll want a pair that will close focus down to about 6 ft. I found
several such models, including the Swift 7x36 Eaglet (6 ft; $299), the
Eagle Ranger 8x42 Platinum Class (5.2 ft; $379), and the Bausch &
Lomb Elite PC 10x42 (5 ft; $800). Two new models from Steiner Optics are
worth noting, too. The Peregrine 8x42 and 10x42 ($795 and $850, respectively)
are compact, roof-prism binoculars that focus from 5.5 ft to infinity;
they're also waterproof, armored, fully multi-coated and phase corrected
for sharp, distortion-free images.
Maximum Light Transmission
Like photographic lenses, some of today's binoculars feature superior
multilayered coatings in addition to wide objective lenses for maximum
light transmission. If you're frequently out in early morning or
late afternoon, you'll appreciate the extra bright view of binoculars
with a twilight factor of 15 or higher. Some models have an even higher
rating. The new Minox BD 12x52 BR A.L.T. ($700; 950 g) with an exit pupil
of 4.3mm boasts a twilight factor of 25 which allows you to view fine
details even in low-light conditions. This premium-grade model includes
rubber-armored aluminum construction, aspherical elements, phase corrected
prisms, M* coatings, and high precision mechanical and optical mechanisms.
Other models with ultrahigh twilight factors include the Leica Trinovid
12x50 BA (24.5 factor; $1200), the Zeiss Victory 10x56 BT (23.7; $1349),
and the Victory B-T* 12x56 (25.92; $1500).
If you're interested in star gazing, check out the very bright Celestron
astrobinocular series with huge objective lenses and wide (4+mm) exit
pupils. The new SkyMaster 15x70, 20x80, and 25x100 porro prism models
($100-$499) are large, heavy binoculars with incredibly high power. For
viewing nearby subjects in darkness, you'll need night vision binoculars
that employ a photocathode tube. This device amplifies ambient light by
accelerating electrons and using a phosphorescent screen for easy viewing.
Night Owl makes several such models, but their new CB-4 ($399; powered
by one 123-A 3v lithium battery) is the most compact and lightweight (6.2x6.2";
2 lbs), and features 4x image magnification; with an optional adapter,
that can be increased to 6.5x.
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Digital Imaging
Do you want to take photos while viewing a distant subject through your
binoculars? If so, you might appreciate one of the binoculars with a built-in
digital camera, such as the Pentax DigiBino DB 100 ($250; 9 oz; powered
by two AA batteries); a 7x17 (roof-prism) model with a 1.6" LCD
monitor, 0.8-megapixel CCD image sensor, and built-in memory for image
storage. While resolution is certainly not high (1024x768 pixels), it's
adequate for making 3x5" prints or for sharing your JPEG images
with friends by e-mail or on a television monitor. The fully automatic
DigiBino DB 100 includes TTL light metering and a 5 frame per second continuous
shooting mode; as with most binoculars, focus control is manual.
Much larger and offering higher resolution, the new Bushnell Instant Replay
8x32 (roof-prism) binoculars ($499; 26 oz; powered by two AA batteries)
can record 2-megapixel images, adequate for making 5x7" or larger
prints. This model can also record 30 second movie clips with .35-megapixel
resolution. In addition to 16MB of internal memory, the Instant Replay
accepts CompactFlash cards with high storage capacity. View the videos
and still images on the LCD monitor or download them to your computer
with the USB cable that's included.
Buy The Right Binoculars
Before deciding on specific binoculars, conduct some research on several
brands and models within your price range. Review the Specifications and
Features charts on manufacturer or retailer web sites, using the guidance
provided in our "Buying Points."
After narrowing the field to several models that should meet your needs,
visit a retail store to try them out. Viewing comfort, and factors such
as clarity, contrast, color rendition, and sharpness, call for a personal
"test drive" for a full evaluation. You'll probably
find that the most desirable binoculars cost more than you had originally
planned to spend. Unless you will need them only occasionally, buy the
best model that you can afford. As with photographic lenses, you get what
you pay for. A poor optical instrument will not reproduce the image clearly
and with frequent use may cause eye strain, headaches, and fatigue. By
investing in high quality binoculars, you will benefit with years of comfortable
and enjoyable viewing.
Binocular Buying Points
Although most photographers are familiar with lenses, some have difficulty
appreciating the finer points of binocular technology. Indeed, some of
the terminology and concepts do differ when dealing with these double-barreled
optics. Before you begin shopping, consider the following information
and recommendations:
Prisms: Used to fold the light path for a shorter barrel--and to
invert the image as in an SLR camera--prisms are standard on all
binoculars. The traditional "porro" prism models are a bit
bulky but provide great contrast, good depth perception, and often, a
wide field of view. "Roof" prisms (denoted by a straight tube)
are light and slim, fairly rugged but more costly to manufacture. Either
type can be excellent but avoid bargain-priced roof-prism models. Many
prisms are made with BK-7 glass but for higher edge sharpness and greater
brightness, look for a model made with high density BaK-4 glass.
The Numbers: All binoculars are designated with a formula
such as 8x25. The first number refers to magnification or power. With
8x binocs, for example, the subject will appear eight times larger than
with the unaided eye. The second number refers to the diameter of the
"objective" lens, or front element, so here, the 25 refers
to 25mm. The wider the objective lens, the greater the light gathering
power and the brighter the image. As noted below, light transmission is
affected by other factors, too, but the following rule of thumb is worth
noting. When comparing binoculars of identical design, the view through
an 8x50 model is twice as bright as through 8x35 binoculars and four times
as bright as through 8x25 binoculars.
Exit Pupil: This is the size of the circle of light that
reaches your eye. The larger the exit pupil, the brighter the view and
the more effective a model will be in very low light. It can be calculated
by dividing the size of the objective lens by the magnification of the
binoculars. (For example, a 7x50 pair has an exit pupil of 7.1mm.)
Image Brightness Ratings: In order to determine the actual light gathering
ability of any model, check the specs for "Relative Brightness Index."
An index around 10 is fine for daytime, but for frequent viewing in low
light, you'll want a model with an index of 25 or higher. Some manufacturers
provide data on the "Twilight Factor" instead. An 8x25 model
may have a twilight factor of 14.14 while the factor for 7x50 binoculars
may be 18.71. Binoculars with a factor of 16 or higher are particularly
useful in low light.
Chemical Coatings: Like photographic lenses, many binoculars'
elements are coated with chemical films to maximize light transmission
while reducing flare. Note the following definitions. Coated: a single
layer on at least one element. Fully coated: a single layer on all elements.
Multi-coated: multiple layers on at least one element. Fully multi-coated:
multiple layers on all air-to-glass surfaces for light loss of 5 percent
or less. Superior coatings are also more effective in reducing glare for
higher contrast and clarity. The prisms in better roof-prism binoculars
are also coated, with "phase coating" that prevents scattering
of incoming light for higher resolution and contrast.
Optical Quality: Like photographic lenses, some binoculars
include aspherical lenses for a clear, sharp view with little distortion.
Some premium-grade models ($400 and up) from Canon, Swift, Minox, Olympus,
and others include a "low dispersion" glass element useful
especially in high-powered binoculars for excellent contrast, clarity,
and color fidelity. When reviewing the optical features, also look for
devices such as a "field flattener" used by Canon and others
(in some models) to produce higher sharpness at the edges of the viewing
area.
Field Of View (FOV): This is a side to side measurement
of the actual area visible through a pair of binoculars, when focused
at a distance of 1000 yards or meters. The higher the power, the narrower
the FOV, of course. The 8x binoculars intended for general viewing often
have a FOV of 300-375 ft. Some manufacturers provide the angle of view,
or "angular field," instead, with 5-6Þ being common.
Multiply that by 52.5 to get the FOV in feet. Models with an FOV of over
400 ft are particularly useful for scanning a large area or following
a moving subject.
Eye Relief: Measured in millimeters, eye relief refers
to the maximum distance from the eyepiece that will make the entire field
of view visible. With some binoculars, you must hold the eyepiece very
close to your eye in order to see the entire field of view. Other models
include "long eye relief"--at least 15mm--useful
for comfortable observation for anyone who must wear glasses while viewing.
In that case, you'll also want fold-down rubber eyecups for excluding
stray light. Of course, you may not need to wear glasses if you select
binoculars with individual diopter adjustment controls for each tube;
this feature works well for many near-sighted individuals, though not
for those with astigmatism.
Manufacturers/Distributors
Bushnell Corporation
(Bausch & Lomb)
(800) 423-3537
www.bushnell.com
Canon U.S.A., Inc.
(800) 652-2666
www.usa.canon.com
Carl Zeiss Sports Optics
(800) 441-3005
www.zeiss.com
Celestron
(310) 328-9560
www.celestron.com
Eagle Optics
(800) 289-1132
www.eagleoptics.com
Leica Camera Inc. (Minox)
(800) 222-0118
www.leica-camera.com
Minolta Corporation
(800) 808-4888
www.minoltausa.com
Night Owl Optics
(212) 229-0297
www.nightowloptics.com
Nikon Inc.
(800) 645-6687
www.nikonusa.com
Olympus America Inc.
(800) 622-6372
www.olympusamerica.com
Pentax U.S.A. Inc.
(800) 877-0155
www.pentaxusa.com
Pioneer Research (Steiner)
(800) 257-7742
www.pioneer-research.com
Swift Instruments, Inc.
(800) 446-1116
www.swift-optics.com
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