Optics Glossary

An adjustment turret is one of 2 knobs located in the middle of the telescopic sight. They are used to adjust the height or side of the reticle. The clicks are divided into ¼ MOA, 1cm or 1/10 MIL.

The ballisitic curve describes the trajectory of the bullet after leaving the gun barrel.

With the Steiner ClicLoc strap attachment, the binoculars are always firmly attached to the strap. The strap can be released and reattached with a single movement. This clever quick-change system allows the exchange of different straps, e.g. from comfort harness to floating strap, in seconds.

By coating the lenses (evaporation of metal oxides or fluorides) the reflection on the glass surfaces is enormously reduced and the light transmission is increased.

The ergonomic ComfortGrips are specially shaped soft thumb cushions with a non-slip surface that provide unique handling.

There are five different world zones because different magnetic forces have to be considered. Only at the equator the field lines run horizontally (inclination = 0°), at the poles the inclination reaches nearly 90° - in between all intermediate values can be found. On the northern hemisphere the north pole of the compass rose is "pulled down", on the southern hemisphere the south pole.

The Click value is the size by which you can change the reticle position by rotating the adjustment towers. It is given in MOA, cm or MIL. Each click changes the hit point position by the specified value.

The specially developed dielectric mirror in the roof prism system of the Wildlife XP 10x44, 8x44 can reflect up to 99% of the incident light.

The dioptre is a unit of measurement for the refractive power of optical lenses. A lens with the focus at 1 m has the refractive power of 1 dioptre.

The Distance-Control-System guarantees a fast and comfortable recognition of animals and birds. Focusing takes place even before the binoculars are on the eye.

The sharpness of the image from the center to the edge decreases for physical reasons. The higher the quality standard of the binoculars, the better the edge sharpness and the lower the waste.

The exit pupil is located shortly before the eyepieces and ideally matches the diameter of the eye pupil of the observer. Formula for calculating the diameter: Lens diameter : Magnification number The larger the diameter of the exit pupil, the better the viewing result at dusk, since the human eye pupil widens all the more at low brightness (approx. 7 mm for young people; approx. 5 mm from the age of 50). During the day, a diameter of approx. 2 to 4 mm is sufficient. However, the exit pupil says nothing about the quality of binoculars.

Term for the connection between the eyepiece and the eye of the observer.

The distance of the eyepiece from the human eye where the full field of view of the product is seen.

Technology specially designed for close-up focusing (from approx. 2 m), which enables fast and convenient focusing thanks to stepless, damped focusing.

The overseeable terrain at a distance of 1000 meters from the object of observation. Usually given in meters. If given in angles, 1°=17.5 m.

New fluoride-containing glass types, which consist mainly of the mineral calcium fluoride, improve the contrast depth and colour fidelity of the image.

A plane at right angles to the main axis of a lens or mirror that displays the best (sharpest) image of an object.

A plane at right angles to the main axis of a lens or mirror that displays the best (sharpest) image of an object.

Steiner's special coating and amplification of individual colour spectra through special coatings results in sharply defined and bright image quality - even in dazzling sunlight or early twilight!

Steiner's specially developed optical technology for Expert series, which guarantees first-class light transmission thanks to a highly complex coating technology.

At distances beyond your point of zero, Hold Over is the amount of adjustment in your point of aim that is needed to compensate for the trajectory or d‍rop of your bullet. Steiner offers several reticles that have hash marks below the center cross hair that correspond to specific distances to help you determine Hold Over. Hold Off is the amount of adjustment that is necessary to compensate for wind drift. At longer ranges, wind can cause your bullet to drift away from your target. The Steiner Plex S1/S7 reticles have cascading dots and lines to help you determine Hold Off at distance.

Geometric luminous intensity: A calculated measure of the brightness value of a pair of binoculars. The higher the luminous intensity, the better the binoculars are suitable for twilight. Formula for calculation: Divide the number of lens diameters by the number of magnifications. Square the result. Relative luminous intensity: While the geometric luminous intensity only takes into account the objective diameter and the magnification, the relative luminous intensity describes the additional increase in performance due to special types of coating and, compared to an uncoated glass, is expressed as a percentage increase (e.g. 60%).

The first number in the model name of a pair of binoculars that indicates how much closer the observed object can be seen to the human eye.

Makrolon® is a high-tech material from the aerospace industry that stands out in particular for its resistance to corrosion and temperature.

Visual comfort par excellence: Allows convenient memory of the personal focus setting - a significant advantage at dusk or when several people use the binoculars.

MIL is an angle specification where 1 width unit is specified for 1000 length units, for example 1m distance in 1000m.

The minute of angle is a unit of circle measurement, at 100yards distance it corresponds to 1.0472 inch. In practice, 1 MOA is given as 1 inch on 100 yards, 2 inches on 200 yards, and so on.

The ultra-thin, hydrophobic surface refinement on ocular and objective lenses protects against all tough environmental influences, is saltwater-repellent and therefore extremely rugged.

Is pumped via special valves into the vacuum of the binoculars and prevents fogging of the lenses or the formation of condensation water in temperature ranges from -40°C to +80°C.

Special rubber armouring resistant to oil, acid and salt water. This armouring protects and extends the life of your binoculars.

This indicates the diameter through which the light passes into the binoculars in millimetres. The larger the objective diameter, the more light can enter and the better the binoculars are suitable for twilight.

The objective lens of a telescopic sight is also called the entrance lens. The diameter is given in millimetres. It corresponds to the value after the x. E g. a 5-25x56 has an objective lens with 56mm diameter. The diameter of the objective lens determines the amount of light that can reach the eye. With a constant magnification, an increase in the objective lens diameter leads to an enlargement of the exit pupil.

The objective lens of a telescopic sight is also called the entrance lens. The diameter is given in millimetres. It corresponds to the value after the x. E.g. a 5-25x56 has an objective lens with 56mm diameter. The diameter of the objective lens determines the amount of light that can reach the eye. With a constant magnification, an increase in the objective lens diameter leads to an enlargement of the exit pupil.

Optical characteristics, e.g. 8x30, 7x50 The first number of binocular markings describes how much larger an object appears in binoculars compared to observation without binoculars. You can find out more under magnification. The second number of characteristics, for example 30, indicates the objective diameter in millimetres. For more details, see Objective Diameter.

The parallax is an obvious error between the reticle and the object. This error usually occurs when the eye travels from a blind spot back to the center when looking through the scope.

The Porro prism system leaves the incident light waves unchanged, which results in a better image quality compared to the roof prism system.

The precision reticle is visible in the entire image section and provides measurements in meters or feet (0.33 m).

The Steiner Wildlife XP 10x44, 8x44 allows you to focus both eyecups individually. The direct adjustment of the eyecups produces a perfect image for both eyes.

The resolution indicates the ability to recognize details and thus the sharpness of the image.

The reticle or crosshair in the scope provides a target reference. Steiner offers various reticles especially for hunting as well as tactical or precision shooting.

The Steiner rotating eyecups are self-locking to always provide the optimum distance to the eyepiece, especially for spectacle wearers. The three levels of the rotating eyecups allow an ergonomic, a classic cylindrical and a spectacle wearer position. If the eyecups do not fit exactly, they can be precisely adjusted using the eyecup fine adjustment mechanism. The ergonomic part of the rotating eyecups provides optimum protection against stray light from the side. Not only do they eliminate annoying reflections, they also ensure an extremely bright image.

The use of roof prisms allows an almost linear incidence of light, although the light waves are slightly shifted. Due to the arrangement of the roof prisms, however, these binoculars can be designed to be particularly slim and handy.

Steiner binoculars are resistant to moisture, dirt and dust due to specific sealing techniques.

Steiner binoculars have soft eyecups that can be easily folded down. This gives spectacle wearers the ideal distance to the eyepiece.

Impressive visual sharpness - without annoying refocusing! With the Sports-Auto-Focus, you only have to adjust the STEINER eyepieces once to your visual acuity and enjoy continuous sharpness from approx. 20 metres. The STEINER Sports-Auto-Focus makes handling particularly comfortable. If both eyes are of the same dioptre strength, simply s‍et both of the adjusting rings on the eyecups to ”0“ and you will see clearly from 20 m to infinity. If not, adjust both oculars individually for razor sharp images. Once adjusted, everything will be sharp and clear from 20 m to infinity for varying distances. Simple use. Also with a single hand only.

Trajectory is the flight of your projectile after it leaves the barrel. Your bullet flies in an arc and the amount of arc depends on the projectile weight and velocity.

Residual amount of the light incident on the objective lens that exits the ocular after it has passed through the binoculars. The more powerful the coating of the lenses of the binocular, the higher the light transmission - the light that hits the eye.

The common diameters for riflescopes are 1 inch, 30mm and 34mm. The larger the tube diameter, the more stable the system. In addition, the number of "clicks" of the height and side adjustment increases with the tube diameter, this is particularly important for Longe Range shooters. The tube diameter also determines the size of the mounting rings for the scope.

A turret is one of two knobs located in the center of the scope tube. They are used to adjust windage and elevation when sighting in. They can also be used to adjust point of aim. They are marked in increments or clicks in ¼ MOA, 1 cm or 1/10 mil increments.

The twilight factor has the most significant impact on resolution or image details. It is a measurement to distinguish efficient viewing in low light 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 e.g. when viewing under low light conditions.

Steiner Ultra-HD Optics deliver the highest level of manufacturing precision and high-quality fluoride glass for absolutely natural colour reproduction, maximum resolution and optimum contrast.

Zeroing is the distance to which your telescopic sight is adjusted. The trajectory of the bullet (ballistic curve) and the line of sight at a certain distance are adjusted congruently. This normally happens at a distance of 100m.


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