More About Construction and Design of Telescopes

Telescopes are equipments that help us to see far off stuff accurately. These equipments help in enhancing the precision of any weapon, like crossbows, handguns, rifles, and compressed air guns, while aiming at an object over long space.

The classification of the telescopes is done based on the diameter of the lens and the magnification power of the lens, i.e. the amount of magnification the lens provides. For example, if a lens is categorized as 20X75, it means that the magnification power of the lens is 20 times and the diameter of the lens used is 75mm. The usage of the telescope should really choose the magnification power of the lens. It is also valuable to opt for telescopes with large diameter since such lens allow more light to come in and improves the vision through the telescope.

The diameter of the lens or the magnification power alone does not make a telescope perfect. Telescopes must be equipped with graticule that is a crosshair, grid, or intersecting mark on the telescope, which helps in aiming long space targets with precision. These reticules are of different types, such as, normal crosshairs or modern graticule with a number of features. The modern form of graticule not only helps in aiming better at the target but also provides help in nullifying the dip in the path of the curve, judging the space of the target, and countering the interference of winds.

Reticule on telescopes can be of two different forms. The differences are based on how the graticule is manufactured. The two forms are engraved graticule and wire reticule.

Engraved graticule is regarded to be the best form of reticule, as it helps in providing stuck-up suitability in shooting the target over long distances. The reticule, which can be a crosshair, grid, chevron, amalgamation of these or any other customized graticule is a line engraved on the glass lens with the help of a shape point, and it is used in the front end of the telescope. The etched lens is mounted carefully to provide a clear line of sight with a graticule to aim correctly. Engraving custom graticule is more pricey and is found on high value telescopes. Telescopes with this type of graticule are the most common in the market. The other form is the wire reticule. Metal wires are used to make these reticules. This is the oldest form of graticule used in telescopes. The wire graticule is placed properly within the sight tube on the telescope. There is a small advantage of using an engraved graticule over a wire reticule. In case the light source is behind the telescope, the latter one reflects the inbound light, which does not provide a perfect distinct reticule, whereas the engraved one ruins black and visible.

The place of the graticule can be on the rear lens on the sight telescope or the front lens. Though, the front graticule is more resilient, rear graticule is preferred more as the size of the target changes while the graticule is stable. Consequently, more and more multi-magnification power telescopes are equipped with rear reticules. The difference is not very clear for telescopes with fixed level of magnification, but for telescopes with varied magnification level, it is more evident. Incase of a front reticule, the size of the same does not change in comparison with the target, but incase of the rear graticule the size of the target is enlarged or minimized. The graticule can also be illuminated in case of dim light environment. Such illuminated graticule comes with brightness adjustment control, consequently, the brightness does not interfere with vision of the person usage the telescope. The brightness adjustment control helps in regulating the light circumstances as per condition.

All telescopes are fitted with adjustment controls in order to aid the person operating the telescope to counter drop in projectile path, wind interferences, passage of the target.

One of the most common adjustment option that is used in the telescopes is the focal point tuning knob for a clear image of the target. The level adjustment knob is used for regulating the sideways passage of the graticule.

Height adjustment knob for regulating the pitch of the reticule. Magnification alteration wheel is used to realize different levels of magnification.

There is the reticule-brightness control knob, which is used for regulating the brightness of an illuminated reticule.

Author: Gia Liu
Condition Source: EzineArticles.com
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