6 what is parallax. Parallax adjustment in optical sights

Let's leave aside the physics of the parallax phenomenon (those who are interested will find where to read about it). The main thing is that it exists and makes life difficult for fans of pneumatics and crossbows. Not only is it inconvenient to aim, but also your accuracy suffers greatly.

This is what the displacement of the point of impact looks like when classical parallax “moons” appear.

Where does it even come from, who is to blame and what to do?

This is caused by the desire of airgunners and some crossbow shooters to acquire “cool” long-focal sights with high magnification. It is they who, at short distances (typical for this weapon), are extremely susceptible to the appearance of moons, the image floating away, etc. And it is precisely on them that manufacturers have to resort to complicating the design by introducing parallax adjustment (focusing) mechanisms. Both using simple AO technology (on the lens) and high-end SF technology (the adjustment flywheel is sometimes a real steering wheel on the side of the sight).

Why the hell would a crossbow or a regular pneumatic spring-piston rifle, intended for plinking or hunting, have a 9 or even 12x scope? Okay, with high-precision shooting carried out from a rest and even from a machine. When shooting handheld, often offhand, we, in addition to parallax, get a cross jumping across a huge target and the resulting desire to “catch” its center, which is one of the main aiming errors. But for some reason this problem is not very relevant for firearms specialists.

What does it look like on a rifled firearm, for which the OP was originally intended? Firstly, shooting is carried out at distances from 100, well, even from 50 meters, at which parallax is no longer observed. Secondly, the multiplicity of military and hunting samples is usually low. Sniper scope PSO-1 (SVD) has characteristics of 4x24.

I (not on a pneumatic) have a more modern “civilian” version 6x36, and its acquisition was caused by age-related vision deterioration. Here, the lens aperture is higher due to the larger aperture, but most importantly, there is a dioptric adjustment of the eyepiece (the same wheel with the “plus” and “minus” signs). Basically, shooting is carried out at distances from 80 to 200 m (direct shot), and then in real hunting no one will shoot, although the diameter of the circle, which coincides with the killing zone of a large animal, is at least 15 cm (5 MOA!). Enthusiasts of high-precision shooting, varmint hunting, and some types of mountain hunting actually use powerful OPs, but in the vast majority of cases, shooting is carried out from point-blank range, at serious distances, from completely different weapons, plus the arrows are no match for us. And, as a rule, they have SF mechanics for parallax adjustment.

On all hunting crossbows, including high-end ones, the standard scope also has modest 4x32 characteristics (see “ “). Just because effective shooting distances are from 20 to 50 meters. In addition, if in crossbow sports the diameter of the “ten” is 4.5 mm (!), then the kill zone of a wild boar or deer is the same 15 cm. Well, why is the 9x multiplicity here?

By the way, for sporting crossbows (as well as rifles) - you will laugh - any optics are generally prohibited, and good old “ring” sights are used. Imagine the level shooting training professional crossbowmen and bullet shooters, almost the majority of whom are girls!

In general, if you are not a fan of BR and other high-precision disciplines, choose a maximum of 6x scope. As an example - “Pilad P4x32LP”, with “tactical” adjustment drums, diopter adjustment and reticle illumination.

These options are quite enough. Pancratic sights are initially more delicate, and a high magnification at any reasonable distances, even for a “supermagnum”, is generally not needed, except when shooting at matches (there is such a thing). By and large, the sight in the top photo is nothing more than a “driver” known to all firearms, successfully used in round-up hunts of wild boar or deer at distances of up to 150 meters.

Moreover, the letter “P” in the name indicates that the sight is also intended for spring-piston pneumatics. Which is characterized by the phenomenon of so-called “double” (multidirectional) recoil, which is not found on any other type of weapon.

Among the budget options, Lipers sights (not long-focus lenses) also showed good resistance to troubles. For money that is quite reasonable in these days, you can buy a device quite high level(pictured “Leapers Bug Buster IE 6X32 AO Compact”).

In addition to diopter adjustment to suit your vision, there are already coated optics, multi-color stepped illumination of the “mildot” reticle, a sealed nitrogen-filled housing, “tactical” correction drums and, most importantly, parallax adjustment.

In general, keep in mind that the complication of the design due to the introduction of additional options (variable magnification, parallax adjustment) worsens the survivability of most OPs in the budget segment. Really high-quality optical-mechanical devices cost completely different money, for which you can buy a bag of ordinary air rifles or a couple of crossbows.

Two main errors when aiming also lead to the phenomenon of parallax:

1. Suboptimal distance of the pupil from the eyepiece lens.
2. Displacement of the pupil from the optical axis of the OP (off-center)

The first is treated by adjusting the distance when installing the sight. Simply put, move the loose OP back and forth until the image lines up with the inside diameter of the spotting scope, with no dark area around the edges of the image.

The second is quite easy to correct through training. Practice the correct position (possibly without shooting): throw the rifle into the firing position and take aim. And so dozens of times, every day. Until you automatically start setting the pupil clearly in the center of the eyepiece.

A little secret that, oddly enough, not everyone knows about. Take a closer look at the behavior of clay pigeon shooters. They tilt their head in advance into the position it will take when aiming, and then raise the weapon, and the comb of the butt simply takes its permanent place under the cheek. At the same time, you no longer need to move your head, trying to find the right position.

In motion, parallax means a change in the location of an object against some background relative to an observer who is in place. This term has gained popularity on the Internet. In particular, a website with dynamic elements in its design looks interesting. Parallax is a way of designing a page on the Internet, used by webmasters to attract a large number of visitors.

What is parallax like?

Parallax scrolling can be used vertically as well as in a straight line. The best example is Nintendo. Many of us remember with nostalgia computer games, represented by the movement of the main characters from the left side of the screen to the right. It is also possible to move downwards along a vertical straight line. often used on the web. To create a vertical slider, you can use JavaScript or CSS 3.

They are characterized by the described three-dimensional spatial effect. The game creators used several background layers. They differ in texture, while movement is carried out with at different speeds.

Don't think that parallax is only about creating a 3D effect. You can move existing icons on the page. Moreover, it looks quite attractive. A particularly good option is to use an individual trajectory for each of them. In this case, different icons are used, moving along different trajectories. This design attracts attention.

Picture coming to life

It's hard to find a site without images. High-quality and demonstrative drawings attract visitors. But the most attention is drawn to various kinds of dynamic images. Indeed, if there is movement when visiting a site, it attracts attention. The likelihood of a resource visitor returning to a dynamic image increases significantly. Did it seem like it was moving or not? Therefore, to attract visitors to the site, it is worth studying such a concept as the parallax effect.

Examples of sites with moving images:

• hvorostovsky.com;
• www.kagisointeractive.com.

As shown in the examples, the perception is improved by a menu that drops down into sub-items. This element saves time for visitors and is therefore attractive to them.

jQuery library

The term jQueryParallax defines the library of the same name. Thanks to it, it is easy to achieve the effect of movement in 3D format. In the jQuery library, a three-dimensional perception is created different ways. One of them is to move background objects horizontally at the same time at different speeds. This library is characterized by the presence of a large number of different kinds of properties. And the displacement described here represents only a small part of its capabilities.

The site looks quite attractive, for the creation of which various modern elements were used. One of them is parallax. Example sites might look like this:

• www.grabandgo.pt;
• www.fishy.com.br;
• www.noleath.com;
• buysellwebsite.com.

jParallax is represented by layers that move with mouse movement. Dynamic elements are characterized by absolute ;). Each of them is characterized by its own size and movement at an individual speed. This can be text or an image (at the request of the resource creators).

Site visitor perception

After this, a person usually pays attention to the fact that the page is designed efficiently, conveniently and competently. This fact usually commands respect. Sometimes curiosity arises to try other elements. Available on the Internet great amount identical sites. How to make your resource special?

If you like the design, the visitor will stay for a longer period. Thus, the likelihood that he will be attracted by the posted information increases and he will show interest. As a result, the person will take advantage of the service, product or promotional offer offered.

Favorite old games

The concept of “parallax” should be familiar to all fans of consoles of the 80s and 90s. This applies to games:

1. Mario Bros.
2. Mortal Kombat.
3. Streets of Rage.
4. Moon Patrol.
5. Turtles in Time.

That is, parallax is a technique that has been used for a fairly long period. These games are indeed remembered with some nostalgia. After all, they seem to be imbued with the character of that period.

The images on the screen are created using a technique called parallax scrolling. It is not surprising that this technique has gained well-deserved popularity. This design concept is quite warmly perceived by those who played in the 80-90s or watched their friends’ leisure time.

Parallax scrolling

Marketers of the world's leading brands have long been using various kinds of technical advances. Thus, it becomes possible to interest even a casual site visitor.

Parallax scrolling was used quite successfully by Nike. The company's original website was developed by designers Weiden and Kennedy. But this design was not preserved. The resource was gradually updated in accordance with modern trends. Activatedrinks.com is an example of a site whose design is reminiscent of the design used by Nike marketers from this period.

There shouldn't be too much dynamics

Do not forget that the design of the site is often key criterion, which guides the visitor. A poorly executed resource usually leaves the user with the impression that the owner company is not serious. But a website with various kinds of attractive design elements indicates the desire of the organization’s owners to interest visitors.

Here it is worth remembering about parallax. This is a wonderful tool. But even they shouldn’t get too carried away. Because the page on which there is a large number of various kinds of moving elements, quite difficult to understand. It is best to make the design moderately stylish and understandable.

Individual elements that require highlighting should be dynamic. There may also be a drawing that is created using layers moving relative to one another. Do not forget that a custom website is designed primarily for visitors. It should not be a masterpiece of a webmaster who has invested all his knowledge. After all, such an approach will only complicate perception.

How to create a movement on the site

How to make parallax? This question interests many website creators. It is not necessary to know the intricacies of writing tags. It is very convenient to use special resources on the Internet. From the large number of available proposals, the following assistants can be distinguished:

1. Plax is a program that is quite easy to use. It tends to give the page movement by moving the mouse.
2. jQuery Parallax Image Slider - jQuery plugin used to create image sliders.
3. Jquery Image Parallax - suitable for designing transparent pictures. Through his use of PNG, GIFs gain depth while being brought to life by movement.
4. Curtain.js is used to create a page equipped with fixed panels. In this case, the effect of opening the curtains is observed.
5. Scrolling Parallax: A jQuery Plugin is to create a parallax effect when scrolling the mouse wheel.

Some more useful plugins

As is known, greatest value has information. And the greater the number of ways to achieve what you want is known, the closer the probability of obtaining the right result. Useful plugins used to create dynamics:

1. jQuery Scroll Path - used to place objects on a specified path.
2. Scrollorama is a jQuery plugin. It is used as a tool for attractive design of the material. Thanks to convenient scrolling, it allows you to “revive” the text on the page.
3. Scrolldeck is a jQuery plugin. It is an excellent solution used as a presentation for websites designed as one page.
4. jParallax renders layers to move based on mouse pointer movement.
5. Stellar.js is a plugin with which any element is designed with the addition of a parallax scrolling effect.

Parallax with cursor snapping

This parallax looks quite impressive. Objects on a site page that seem motionless at first glance move when approached. It seems to come to life and follow the element being moved.

First you should stop at the drawing. The required image is placed in a frame, and its edges must be hidden. The method is very simple, and the resulting drawing looks quite attractive.

The parallax effect for a website is a wonderful design method. Its use indicates that due care was given to the creation of the resource. Therefore, it is worth paying attention to the services offered or information to read. Such sites look more advantageous against the background of identical, but simply designed resources.

In “experienced” conversations, when it comes to optical sights, the concept of “parallax” often comes up. At the same time, many companies and models of sights are mentioned, and various assessments are made.

So what is parallax?

Parallax is the apparent shift in the target image relative to the reticle image when the eye moves away from the center of the eyepiece. This occurs due to the fact that the target image is not focused exactly in the focal plane of the reticle.
Maximum parallax occurs when the eye reaches the end of the scope's exit pupil. But even in this case, a scope with a constant 4x magnification, adjusted for parallax at 150 m (at the factory), will give an error of about 20 mm at a distance of 500 m.
At short distances, the parallax effect has virtually no effect on the accuracy of the shot. So, for the scope mentioned above at a distance of 100 m, the error will be only about 5 mm. It should also be kept in mind that when you keep your eye centered on the eyepiece (on the optical axis of the scope), the parallax effect is practically absent and does not affect shooting accuracy in most hunting situations.

Sights with factory parallax adjustment

Any sight with a fixed lens focusing system can be adjusted against parallax only at one specific distance. Most scopes have a factory parallax adjustment of 100-150 m.
The exceptions are low magnification sights, oriented for use with a shotgun or combined weapon (40-70 m) and so-called “tactical” and similar sights for long-distance shooting (300 m or more).

According to experts, you should not pay serious attention to parallax, provided that the shooting distance extends within: 1/3 closer... 2/3 further than the distance the sight is factory adjusted for parallax. Example: "tactical" sight The KAHLES ZF 95 10x42 is factory parallax adjusted to 300 m. This means that when shooting at distances from 200 to 500 m you will not feel the parallax effect. In addition, when shooting at 500 m, the accuracy of the shot is influenced by a lot of factors related, first of all, to the characteristics of the weapon, the ballistics of the ammunition, weather conditions, the stability of the position of the weapon at the time of aiming and firing, leading to a deviation of the point of impact from the aiming point by values ​​significantly exceeding the deviation caused by parallax when firing from a rifle clamped in a vice in an absolute vacuum.
Another criterion: parallax does not appear significantly until the magnification factor exceeds 12x. Another thing is scopes for target shooting and varmint, like, say, 6-24x44 or 8-40x56.

Sights with parallax adjustment

Target shooting and varmint require maximum aiming accuracy. To ensure the required accuracy at different shooting distances, sights are produced with additional focusing on the lens, eyepiece or on the body of the central tube and a corresponding distance scale. This focusing system allows you to combine the target image and the image of the aiming mark in the same focal plane.
To eliminate parallax at a selected distance, you must do the following:
1. The image of the aiming mark must be clear. This must be achieved using your scope's focusing mechanism (diopter adjustment).
2. Measure the distance to the target in some way. By turning the focusing ring on the lens or the handwheel on the body of the central tube, set the measured distance value opposite the corresponding mark.
3. Securely secure the weapon in the most stable position and look through the scope, concentrating on the center of the reticle. Raise your head slightly and then lower your head. The center of the aiming mark must be absolutely motionless in relation to the target. Otherwise, perform additional focusing by rotating the ring or drum until the movement of the center of the mark is completely eliminated.
The advantage of sights with parallax adjustment on the body of the central tube or on the eyepiece is that when adjusting the sight, the shooter does not need to change position when preparing to shoot.

Instead of output

Nothing happens for nothing. The appearance of an additional adjustment unit in the sight cannot but affect the overall reliability of the design, and, if properly executed, the price. In addition, the need arises to think about additional settings in stressful situation cannot but affect the accuracy of your shot, and then you yourself, and not your sight, will be to blame for the miss.

The above values ​​are taken from materials provided by (USA) and (Austria).

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The company "World Hunting Technologies" is official representative on the territory of the Russian Federation, optical sights of the brands Kahles, NightForce, Leapers, Schmidt&Bender, Nikon, AKAH, Docter. But in our assortment you can also find sights from other famous manufacturers. All scopes sold by us come with a full manufacturer's warranty.

Modern optical sights for all types of hunting, sporting, benchrest, varmint, sniping, tactical use and for installation on pneumatic rifles. Sales, selection of brackets, installation and warranty (post-warranty) service of optical sights in St. Petersburg and throughout Russia!

Technical On-Line consultations on sights- Alekseev Yuri Anatolyevich (9:00 - 23:00 MSK):
Tel. 8-800-333-44-66 - free call throughout Russia:
Extension numbers - 206 (forwarding to my mobile)
Skype: wht_alex

Knowing the distance between observation points D ( base) and the displacement angle α in radians, you can determine the distance to the object:

For small angles:

The reflection of the lantern in the water is significantly shifted relative to the practically unchanged sun

Astronomy

Daily parallax

Daily parallax (geocentric parallax) - the difference in directions to the same body from the center of mass of the Earth (geocentric direction) and from given point on the Earth's surface (topocentric direction).

Due to the rotation of the Earth around its axis, the position of the observer changes cyclically. For an observer located at the equator, the parallax base is equal to the radius of the Earth and is 6371 km.

Parallax in photography

Viewfinder parallax

Viewfinder parallax is the discrepancy between the image visible in an optical non-mirror viewfinder and the image obtained in the photograph. Parallax is almost unnoticeable when photographing distant objects, but is quite significant when photographing close objects. It arises due to the presence of a distance (basis) between the optical axes of the lens and viewfinder. The parallax value is determined by the formula:

where is the distance (basis) between the optical axes of the lens and viewfinder; - focal length of the camera lens; - distance to the aiming plane (subject of shooting).

Viewfinder parallax (sight)

A special case is sight parallax. Parallax is not the height of the sight axis above the barrel axis, but the error in the distance between the shooter and the target.

Optical parallax

Rangefinder parallax

Rangefinder parallax is the angle at which an object is visible when focusing using an optical rangefinder.

Stereoscopic parallax

Stereoscopic parallax is the angle at which an object is viewed with both eyes or when photographed with a stereoscopic camera.

Time parallax

Temporal parallax is a distortion of the shape of an object by parallax that occurs when shooting with a camera with a curtain shutter. Since exposure does not occur simultaneously over the entire area of ​​the photosensitive element, but sequentially as the slit moves, when shooting fast moving objects their shape may be distorted. For example, if an object moves in the same direction as the shutter slit, its image will be stretched, and if in the opposite direction, it will be narrowed.

Story

Galileo Galilei suggested that if the Earth revolved around the Sun, this would be noticeable by the variability of parallax for distant stars.

The first successful attempts to observe the annual parallax of stars were made by V. Ya. Struve for the star Vega (α Lyrae), the results were published in 1837. However, scientifically reliable measurements of the annual parallax were first carried out by F.V. Bessel in 1838 for the star 61 Cygni. The priority of the discovery of the annual parallax of stars is recognized by Bessel.

see also

Literature

• Yashtold-Govorko V. A. Photography and processing. Photography, formulas, terms, recipes. Ed. 4th, abbr. - M.: “Art”, 1977.

Links

• The ABC's of Distances - a review of measuring distances to astronomical objects.

Wikimedia Foundation. 2010.

See what "Parallax" is in other dictionaries:

- (astro.) the angle formed by visual lines directed at the same object from two different ones. points. Once the parallax of an object and the distance between two points from which this object was observed is known, then the distance of the object from... ... Dictionary foreign words Russian language

- (from the Greek parallaxis deviation) 1) a visible change in the position of an object (body) due to the movement of the observer’s eye. 2) In astronomy, a visible change in the position of a celestial body due to the movement of the observer. There are parallax,... Big Encyclopedic Dictionary

parallax- the apparent displacement of the object in question when the angle of its perception changes or the observation point moves. Dictionary practical psychologist. M.: AST, Harvest. S. Yu. Golovin. 1998. parallax... Great psychological encyclopedia

PARALLAX, the angular distance by which a celestial object appears to move relative to more distant objects when observed from opposite ends of the base. Used to measure the distance to an object. Star parallax... ... Scientific and technical encyclopedic dictionary

PARALLAX, parallax, husband. (Greek parallaxis evasion) (astro.). An angle that measures the apparent displacement of a luminary when an observer moves from one point in space to another. Daily parallax (the angle between the directions to the star from this place … Dictionary Ushakova

- (from the Greek parallaxis deviation) the apparent displacement of the object in question when the angle of its perception changes ... Psychological Dictionary

- (from the Greek parallaxis deviation) in aviation, astronautics, lateral displacement of the plane of the final orbit aircraft relative to the starting point, usually measured along an arc great circle from the launch point of the aircraft to the trail... ... Encyclopedia of technology

- (from the Greek parallaxis deviation) in astronomy, a change in the direction of the observer astr. object, when the observation point is shifted equal to the angle under the eye from the center of the object, the distance between the two positions of the observation point is visible. Usually used P.,... ... Physical encyclopedia

Noun, number of synonyms: 1 offset (44) ASIS synonym dictionary. V.N. Trishin. 2013… Synonym dictionary

parallax- The apparent change in the position of an object relative to another object when the point of view changes... Dictionary of Geography

Parallax (from the Greek παραλλάξ, from παραλλαγή, “change, alternation”) -

— change in the apparent position of an object relative to a distant background depending on the position of the observer.

Parallax is used in geodesy and astronomy to measure the distance to distant objects. Based on the phenomenon of parallax binocular vision. Also from the word parallax comes the non-systemic unit of distance measurement known to many from science fiction, and not only films, the parsec.

The name comes from allax arcsecond pairs and denotes the distance to an object whose annual parallax is equal to one arcsecond (for example, a parsec is 3.26 light years or 30.85 trillion kilometers!).

So why is it necessary to adjust parallax on an optical sight?

But why? The optical system of the sight is designed in such a way that the image of a distant target is projected by the lens into the plane where the aiming reticle is located. Parallax in sights is the discrepancy between the plane of the target image formed by the lens and the plane of the aiming reticle. This can be either the front focal plane of the lens (FFP) or the rear focal plane of the eyepiece (SFP). The nature of parallax is a change in the so-called solid angle when the distance to the target changes. If the target is brought closer, the angle increases and thereby increases the rear segment of the lens, spreading the focal plane of the lens and the reticle into different parallel planes. This is what causes parallax! And if the parallax is not adjusted, it will introduce an error when shooting depending on the position of the shooter’s eye relative to the axis of the sight!

You can notice parallax in the following way: if the sight has an aiming reticle in the focal plane of the lens, then when the eye moves perpendicular to the axis of the sight, you can notice that the target image ‘floats’ relative to the center of the reticle and the aiming point seems to ‘move’ away from the target.

In most modern sights, the reticle is located in the rear focal plane of the eyepiece, and in such sights, parallax is manifested by the blurring of the aiming reticle and the inability to see simultaneously and with equal clarity the image of the target and the aiming reticle, if the target is not at an infinitely distant distance.

In order to simultaneously see the image of the target and the aiming reticle with equally high clarity at an infinitely distant distance, you need to make adjustments to the settings optical system sight for each specific firing range, changing the interfocal distance of the lens and eyepiece.

To eliminate parallax in sights, there is a lens focusing mechanism that allows you to place the image from the lens exactly in the plane of the aiming reticle.

Typically, this is done by moving the entire lens system of the lens or just the inner part.

There are two types of parallax adjustment devices - AO (AdjustableObjective) and SF (SideFocusing).

With AO, the parallax adjustment ring is located directly on the scope lens. A scale indicating the focusing distance is applied to the lens barrel.

Parallax is eliminated by rotating the ring on the lens and thus adjusting the lens to the desired shooting distance. This method is more common due to its ease of implementation and low cost. The disadvantage of this method is the inability to turn the parallax adjustment ring while not in the shooting position.

With SF, the parallax adjustment mechanism is located on the side of the scope and is sometimes equipped with a large removable wheel for convenient and smooth parallax adjustment.