NOBLEX NF 7x50 C advanced

NOBLEX NF 7x50 C advanced

For the special demands on board

NF 7x50 C advanced binoculars are a top product of fine mechanical precision with the highest demands on optical imaging performance. They are manufactured according to the latest optical calculation and optical technology and are solid in workmanship

binoculars are designed to be worn by eyeglass wearers, are argon-filled and water pressure-tight, and are equipped with an illuminated compass and reticle and can be used for distance measurement.

large 45 mm compass of the NOBLEX NF 7x50 C advanced, because it is fluid-damped, reliably indicates the north direction even in stormy seas. The finely scaled reticle supports reliable bearing. Even in poor light conditions, for example at dusk, the high transmission of the special glass used is convincing.

In the days before the GPS system, water sports enthusiasts often determined their location with a so-called cross bearing

.

For this, prominent points on land that were visible from afar, such as church steeples, grain silos, lighthouses or tall factory chimneys, were aimed at using a small hand-held bearing compass. Depending on the direction of the target, a degree can be read on the compass via the sighting device, which is called bearing. Such a bearing can logically lie between 0° and 360°. With the bearing of two different points on land from the same location, the above-mentioned cross bearing has been taken. After that, the bearings have to be drawn into the nautical chart with a triangle and a pencil. Where the two lines (the bearings) cross is the viewpoint of the observer or boat.

To simplify this bearing process and also to be able to take bearings on points further away, a small bearing compass was built into binoculars

.

The first binoculars for civilian use came onto the market around 1970. Before that, this technology was only found as a permanently installed system on large warships, which used it to aim their guns. In today's compass binoculars for the civilian sector, the scale of the compass is now reflected into the beam path. The compass calotte, i.e. the housing in which the compass rose (with the degree numbers) is located and can rotate freely, is found in most cases as a mounted or attached part on one of the binocular halves (usually on the right). The compass rose is brought into the field of view of the binoculars by the reflection. Depending on the manufacturer, this cuts the field of view in the lower area by a good 30 percent. Here, the compass rose is now visible as a continuous band.

A military reticle is usually used as a sight, which is also supposed to be useful for distance estimations by size comparisons. To allow compass bearings even in bad weather conditions or at night, an illumination is built in, powered by a coin cell. However, with many binoculars on the market, the illumination has to be switched on even in normal weather conditions, because the window on the top of the compass calotte, which is necessary for light incidence, is too small in size or is often intuitively covered by the fingers of the (right) hand when holding the binoculars. But even if there is enough brightness (daylight), with many models the reading process is not an easy task. This is due to the often too small diameter of the compass rose. Only a large compass rose with a clearly separated degree division also offers a clear picture in the reading window.

addition, only a larger rose offers enough space for a labeling of the tens of degrees, e.g. 10°, 20°, 180°, 270°, but this number division is absolutely necessary for quick orientation on the water, especially in dangerous or emergency situations.

Only with their help, other observers or approaching rescue vehicles can be quickly and accurately instructed

.

Since boats and ships are usually disturbed by swell, engine and wind influences, the bearing and damping of the compass rose plays an equally important role when reading the bearing in the compass binoculars. If the rose were not surrounded by a liquid in its housing, vibrations, oscillations and boat movements would be transmitted directly and the image in the binoculars would constantly shake and be out of focus. To avoid this, good compass domes are filled with silicone oil, which dampens external influences and protects the compass rose in its housing from dancing around.

However, this oil must not be too thick, because the damping influence also increases the so-called tracking error. Tracking error is the time it takes for the compass rose to follow a slew of the binoculars and settle on a new bearing, i.e., a new number of degrees. The bearing of the compass rose also has a large effect on this delay time. Good compasses have a small tip made of gemstone on which the compass needle or rose rotates. Only this hard material guarantees an almost frictionless rotation in the long