Here you will find useful answers to the most frequently asked questions about riflescope technology, reflex sights, and binoculars.

 

Scope technology

What happens to the reticle when changing magnification?

The behavior of the reticle when changing magnification is determined by its position in the rifle scope. A telescopic sight has two image planes. If the reticle is in the first image plane, it is also enlarged when the magnification is changed and the size ratio (coverage) of the reticle to the target always remains the same. This makes it possible to estimate the distance to the target at all magnification levels with a known bar spacing of the reticle. When reticle in the 2nd image plane, the size of the reticle always remains constant. This means that different degrees of coverage of the reticle also occur at different magnification levels. Estimating the distance is hardly feasible here. However, with this variant, a clean shot is still possible even at a greater distance, since the aiming mark covers very little of the target.

 

What is the difference between illuminated daylight reticle and twilight reticle?

Until the early 1990s, only riflescopes without illumination were in circulation. With the agreement that an illuminated reticle does not violate the federal hunting law, riflescopes with illuminated reticle experienced a real boom and are now standard in hunting operations.
It is also standard that the brightness of an illuminated reticle can be regulated. In the case of twilight reticle, this adjustable brightness curve is adapted to eye perception at night. This prevents the target from fading and eye strain. In most cases, the basis is reticle 4. During daytime use, reticle 4 is used as usual without activating the illumination.
Due to further developments in the field of diode technology, it is now possible to also offer riflescopes with a daylight reticle. As the name suggests, this lighting variant is also intended for daytime use. Due to the high performance of today's diodes, it is possible to make the target mark visible in almost all lighting conditions. Here, of course, the brightness control is also adapted to the natural perception of the eye.

 

How long is the battery life?

The service life of batteries, regardless of the type, is largely dependent on the frequency of use and environmental influences. The ambient temperature plays a decisive role here. The type of illuminated reticle is also decisive for the durability of the battery. Illuminated daylight reticles consume more power than illuminated twilight reticles due to their greater brightness. If riflescopes are often used in cold temperatures, the battery voltage will quickly drain. It is recommended to change the battery at the beginning of the hunting season. So you are on the safe side. A spare battery in your warm trouser pocket also helps to avoid unpleasant surprises on a wintry drive hunt.

 

What is the effect of the combination of scope and goggles?

Glass wearers always have a small handicap compared to non-glass wearers. The use of additional lenses (glasses) can cause imaging errors, which the observer perceives as a changed visual impression and possibly as disturbing.
Every telescopic sight has a diopter adjustment that is able to compensate for a shooter's ametropia to a certain degree. However, people who wear glasses (mainly people corrected for distance) should also wear their glasses when shooting. Especially shooters with astigmatism should leave their glasses on when shooting.Astigmatism cannot be corrected by adjusting the diopter on the riflescope, since this ametropia is too individual
Image errors occur particularly frequently when shooting with progressive lenses. Due to the construction of these lenses, the shooter only has a narrow visual channel. If the shooter deviates from this visual channel when aiming, image distortions occur, which can manifest themselves in star-shaped, frayed illuminated dots or curved reticle bars. In addition, the image as such becomes blurred.
The choice of glasses frame is also a crucial criterion. If the frame is too small, the shooter may look directly at the edge of the frame while shooting. Depending on the ametropia, this can result in image duplication or visual field failures. It is therefore important to ensure that the lenses are sufficiently dimensioned, especially upwards.

 

Reflex Sights

How is the NOBLEX sight mounted?

The NOBLEX sight can be mounted on almost all weapons. Your gunsmith will give you expert advice on how to mount the gun. Leading mount manufacturers offer the corresponding NOBLEX sight adapter plates for almost all gun mounts. An adapter plate is even available for the high-quality SEM (Suhler Einhak-Montage), which, however, has to be individually adapted to the weapon by a competent gunsmith.

 

How far can I shoot with the NOBLEX sight?

The NOBLEX sight has been developed for shooting distances of 20 m to a maximum of 60 m - i.e. typical driven hunt distances. From a purely technical point of view, it is certainly possible to shoot at greater distances. However, due to the simple enlargement and the increasing point coverage, a clean shot and a safe address become much more difficult.

 

Do I have to keep both eyes open when aiming?

It is possible to aim with both eyes or just one eye. The advantage of aiming with both eyes open is the use of the largest possible field of view. Due to the simple magnification, there are no disturbing double images when aiming with both eyes, where the brain is forced to hide an image impression.

 

Why doesn't the dot appear round?

Point mapping works on the basis of total reflection. Like every reflection, this one can also be influenced by certain factors. Certain light sources are decisive here, as they can trigger disturbing side reflections and thus make the point no longer appear circular. The sun, which is low and oblique from the front, is one of these disturbing light sources.
Another major influencing factor is the human eye. Our eyes tend not to depict point sources of light as such, especially when a certain light intensity is exceeded. This phenomenon can be observed very well with a burning candle. If you look directly into the flame, a jagged corona appears around it. This impression is created solely by the image in the eye.
Ametropia, especially astigmatism, can also cause punctiform light sources to appear non-round or jagged. This ametropia does not necessarily have to affect everyday visual tasks and therefore goes unnoticed. When looking at a point light source, it usually appears jagged on one side.

 

Binoculars

Where can NOBLEX binoculars be purchased?

NOBLEX binoculars are available from hunting shops, gunsmiths, opticians and photo shops.

 

Which is the right pair of binoculars?

The range of models is as varied as the field of application of binoculars. But one thing applies to all. The type of use determines the type of binoculars. If you need binoculars for hiking, for bird watching, for stalking, for a blind in daylight or for a Sunday walk, you will opt for a model with a compact design and a lens diameter between 25 mm and 42 mm. Binocular models with a lens diameter of 50 mm or more are mostly used when hunting from a blind or for stationary observations.

 

What is the difference between porro and roof prism binoculars?

Binoculars with Porro prisms can be recognized by the fact that there is a clear offset between the lens and the eyepiece, with the lenses usually being set outwards in the binocular arrangement of two telescopes. This design goes back to the version patented by Ernst Abbe in 1893, which founded binoculars. Porro prisms come in two different configurations, with Porro systems of the first type predominating today. From around the 1920s, binoculars with other prism erecting systems were also developed and manufactured in large numbers, with a reflective surface designed as a roof edge being typical here. These systems can be designed without an axis offset between the incoming and outgoing beam. Typical prism systems with a roof edge are named after Abbe-König, Uppendahl or Schmidt-Pechan, which has probably found the widest distribution. Optical performances:

• Porro prism systems avoid the system-related disadvantage of a prism set with a roof edge in the form of polarization effects, the effect of which in this type of reversing system can only be reduced by the highest level of accuracy and a phase-correcting coating on the roof edge.
• In a Porro system, the reflection on the catheti surfaces of the prisms takes place using the effect of total reflection and is therefore almost loss-free. No sensitive and transmission-reducing mirror layers are required.
• By cementing the two individual prisms used, for example, with NOBLEX, the number of optically effective surfaces is reduced from 8 to 6 and thus the possibility of negative influences on the imaging performance. At the same time, the transmission is increased by avoiding two glass-air surfaces. With a roof edge system according to Schmidt-Pechan, there are 10 effective surfaces that influence the image.
• The clear beam guidance through the prism system and the prevention of light interference through a suitable design of the prism holder enable a high contrast of the image. The occurrence of brightening in the light outlet on the eyepiece side (side pupils), which cannot always be reliably avoided even with high-quality roof prism glasses, is completely ruled out and enables high brilliance.
• With a porro prism system, much larger beam bundles can be realized, which are guided through the prisms without loss. Typically, with the same lens diameter, the light bundles are twice as large as with roof prism glasses, which are fully transmitted. This also results in a brighter image towards the edge of the image than is usual with roof prism glasses and better suitability for twilight.

(Source: A. Koehler from www.akoehler.de)

 

Why large lens diameters for dark observations?

The size of the exit pupil of the binoculars is decisive for the amount of light reaching the eye. Since this diameter is calculated from the quotient of lens diameter and magnification, the lens diameter has a significant influence on the binoculars' suitability for use at night.

 

What effects does the exit pupil diameter have on observation comfort?

The size of the exit pupil of the binoculars should ideally have the same diameter as the entrance pupil of the observing eye. Only then can the full light output of the binoculars also be used by the observer. The pupil size of the human eye is individual. Although the opening capacity of the eye pupil changes over the course of life, it is still not advisable to give general figures. For example, not every 20-year-old has a maximum pupil opening of 7 mm and not every 60-year-old has a pupil size of 3 mm. But one thing can be said with certainty: a binocular exit pupil that is larger than the pupil of the eye brings advantages in terms of observation comfort. The edges of the aperture are less perceived and the restlessness of the hand is less noticeable through dancing and shaky edges of the field of view. The user will not be able to use the full light output of the binoculars, but will be compensated with a calmer image.

 

Why do lenses have to be compensated and how do I recognize the compensation?

Lens must be coated to ensure maximum light transmission. For physical reasons, however, it is impossible to achieve 100% transmission. Therefore, residual reflections can still be seen on binocular lenses, which appear in different colors depending on the type of coating.
The color appearance of an anti-reflective coating (coating layer) results from the not completely linear progression of the residual reflection over the wavelength range. This residual reflection is essentially determined by the type of anti-reflection coating (single layer, multi-layer coating or broadband anti-reflection coating), the position of the reflection minimum, the recipe used for the layer system (material selection, layer thickness and layer sequence), the refractive index of the base material and manufacturing variations (deviations in the layer thickness and position within the vaporization system).
Typically, the traditional single coat of MgF2 has a blue tint. Multi-layer coatings often appear violet, but can also have any other color, for example blue, if the reflection minimum is shifted to red.
Modern broadband anti-reflection coatings are often slightly green because they are within the very large spectral range in which the reflection is very small is, in the central area, i.e. green, the reflection is slightly higher. This is already perceived as a hue.
(Source: A. Köhler from www.akoehler.de)