Nikon 7237 Action 7×35 EX Extreme All-Terrain Binocular
Description
The Monarch ATB 42mm with dielectric high-reflective
Multilayer Prism coating binocular features brighter, sharper colors, crisp
and drastically improved low-light performance. A new body style provides
unparalleled strength and ruggedness in a package that is comfortable to carry
all day. With rugged rubber Armor for added durability and a firm grip even in
the worst conditions, Nikon guarantees every ATB to be 100% waterproof and fog
proof, each is backed by Nikon 25 year limited warranty and No-Fault
repair/replacement policy. The new Monarch ATB 42mm with dielectric high-
reflective Multilayer Prism coating binocular is available in 8×42, 10×42 and
12×42. It is also available in team Realtree models with the Realtree apg HD
camouflage pattern. From the Manufacturer The Monarch ATB 42mm with Dielectric
High-Reflective Multilayer Prism Coating binocular features brighter, sharper
colors, crisp and drastically improved low-light performance. A new body style
provides unparalleled strength and ruggedness in a package that is comfortable
to carry all day. With rugged rubber armor for added durability and a firm
grip even in the worst conditions, Nikon guarantees every ATB to be 100%
waterproof and fogproof, each is backed by Nikon’s 25 Year Limited Warranty
and No-Fault Repair/Replacement Policy. The new Monarch ATB 42mm with
Dielectric High-Reflective Multilayer Prism Coating binocular is available in
8×42, 10×42 and 12×42. It is also available in Team REALTREE models with the
REALTREE APG HD camouflage pattern. Technical Specs Additional Action EX
Highlights: BaK 4 High Index Roof Prisms Tripod adaptableLong eye relief for
eyeglass wearers Warranty Information Nikon is dedicated to quality,
performance and total customer satisfaction. If your Nikon binocular, Spotting
Scope or Fieldscope requires service or repair not covered by our 25 Year
Limited Warranty, Nikon will repair or replace it (even it was your fault) for
just $10, plus return shipping and handling. Excludes – StabilEyes, Laser
Rangefinders and Spotting Scope/Fieldscope eyepieces. FAQ’s Real field of view
Real field of view is the angle of the visible field, seen without moving the
binoculars, measured from the central point of the objective lens. The larger
the value is, the wider the viewfield available. For example, binoculars with
a wider field of view are advantageous for locating fast-moving wild birds
within the viewfield. This also applies for finding small nebulas or a cluster
of stars in astronomical observations. Apparent field of view Apparent field
of view is the angle of the magnified field when you look through binoculars.
The larger the apparent field of view is, the wider the field of view you can
see even at high magnifications. With the conventional method used previously,
the apparent field of view was calculated by multiplying the real field of
view by the binocular magnification. (With this formula, apparent field of
view wider than 65˚ is called wide field of view.) After revision, Nikon’s
figures are now based on the ISO 14132-1:2002 standard, and obtained by the
following formula: tan ω’ = τ x tan ω Apparent field of view: 2ω’ Real field
of view: 2ω Magnification: τ (With this formula, apparent field of view wider
than 60° is called wide field of view.) For example, the apparent field of
view of 8x binoculars with an 7.0°real field of view is as follows: 2ω’ = 2 x
tan(r x tan ω) = 2 x tan(8 x tan 3.5) = 52.1° Relative Brightness Relative
brightness value is obtained by squaring the diameter of the exit pupil. The
greater the relative brightness is, the brighter the image will be. With 8×42
binoculars, the brightness is (42÷8)2= 28.1. This means that if the
magnification is the same, the larger the effective diameter of the objective
lens, the brighter the image will be. Do binoculars with the same exit pupil
offer the same brightness? No. Brightness may vary even if the exit pupil is
the same. This is because the amount of light reaching the viewer’s eyes
varies according to the number of lens elements and quality of lens/prism
coatings. Superior optical design and highquality coating greatly contribute
to the brightness of binoculars. Brightness values specified in product
brochures, etc. are theoretical ones calculated in the design process. Please
note these factors when comparing actual brightness values. Prisms Prisms are
what let you see a correctly oriented image when you look through a pair of
binoculars. There are two types of prisms in common use, Porro prisms and roof
prisms. Roof prisms are essentially in line inside the optical tubes, and make
for a more compact set of binoculars. Roof prism binoculars have straight
tubes (the front/objective lens is in line with the rear/ocular lens), and are
therefore more compact, an important consideration for the sportsman. They
usually have two pivot points between the tubes, and are more difficult to
adjust to the spacing of your eyes. Roof prisms can give an optical image
equal to the best Porro prisms, but for technical reasons they usually do not.
To be really good, roof prism binoculars have to be in the high price class.
Do not attempt to economize on roof prism binoculars. Porro prism binoculars
can be identified by their offset tubes; the objective lens is not in line
with the ocular lens. The front lenses are usually closer together than the
rear lenses, but the reverse can also be true, particularly in compact models.
The Porro prism design is usually optically superior to the roof prism design,
especially in medium priced class binoculars. Porro prism binoculars have a
single pivot between the two halves of the binocular, and are therefore easy
to adjust for the distance between your eyes. Like roof prisms, not all Porro
prisms are created equal. BAK-4 prisms are the best; they are made of superior
optical glass that produces clearer images. These are what you want in your
binoculars. BK-7 prisms are also used, usually in lower priced binoculars.
These are satisfactory, but they are inferior to the BAK-4 prisms. Some
manufacturers will not tell you what kind of prisms they use, usually because
they are of inferior quality. BAK-4 prisms show a truer round, which
translates to better light transmission and edge-to-edge sharpness Prism
Coatings Multilayer coating is also applied to prisms to raise transmittance.
A roof prism system has one surface that does not feature total internal
reflection, so vapor deposition with metals, etc. must be used to raise the
reflectivity of this surface. Also, phase-correction coating on roof surface
ensures high-contrast images. Binoculars’ brightness and contrast are
affected by not only prism coatings, but also the number of objective lens and
eyepiece lens, and types of coatings. Phase-correction coating A roof (Dach)
surface can cause phase shift of light that affects image resolution. This
phenomenon is caused by phase differences arising from total light reflection
on a roof (Dach) surface and it can occur with even a perfectly processed
prism. Phase-correction coating is applied to the surface to minimize loss of
resolution, ensuring high-contrast images. Twilight Factor The factor that has
the greatest impact on resolution or image detail, will be dependent upon the
amount of light available during the time of observation. During daylight
hours, when your eye pupil size will be only about 2 to 3mm, magnification
will be the principal factor in image resolution. At night, with the eye pupil
dilated to 6 to 8mm, aperture size is the controlling factor. In twilight
conditions both of these factors control resolution effectiveness and the
twilight factor is the term that compares binocular performance under these
conditions. The twilight factor is calculated by taking the square root of the
product of the magnification and the aperture. The higher the twilight factor,
the better the resolution of the binocular when observing under dim light
conditions. For example, a 10 X 40 (twilight factor 20) would effectively
resolve better under these conditions than a 7 X 35 (twilight factor 15.4)
even though the 10 X 40 has a smaller exit pupil. Remember, however, that the
twilight factor does not take into account the transmittance or quality of the
optical system.
Features:
- Package Dimensions: 7.95 L x 3.78 H x 7.32 W (inches)
- Package Weight : 2.51 pounds
- Country of Origin : China
- Rugged Waterproof, Fog proof Construction
Product Details:
- Brand: Nikon
- Age Range (Description): Adult
- Special Feature: Twist-Up/Click-Stop Rubber Eyecups; Comfortable Long Eye Relief, Lead- and Arsenic-Free Eco-Glass; Nitrogen Filled, Water and Fogproof; Large Center Fast-Focus Knob See more
- Objective Lens Diameter: 35 Millimeters
- Magnification Maximum: 8
- Product Dimensions: 7.9 x 7.2 x 3.3 inches
- Item Weight: 1.8 pounds
- Item model number: 7237
- Batteries: 1 A batteries required.
- Is Discontinued By Manufacturer: No
- Date First Available: September 16, 2003
- Department: unisex-adult
- Manufacturer: Nikon Sport Optics
- Country of Origin: China