Binoculars and telescopes are used for scientific studies of the universe. It is also used in navigation purposes for ships and vessels. Binoculars are also used in law enforcement units and in the marines for intelligence and warfare purposes. Generally, telescopes and binoculars have the ability to zoom in at close-ranged objects that are beyond our naked eyes.



Before choosing the finest of the telescopes and binoculars, we must learn the basics and how it works. Basically for telescopes, there are two main types. These are the refractors or spyglass type and the reflector.

It is important to choose telescopes by their aperture and not to give so much consideration on its magnification abilities. This means you should look for the diameter of the lens or its mirror. The aperture plays a significant part of the telescope. The more light that it collects the clearer and more focused will it be. Therefore, it is best if you choose those with larger aperture; refractor or reflector does not matter. Telescopes having 75 mm or 3 inches of apertures are refractors and telescopes with bigger apertures are called reflectors.

With the smaller refractors with apertures at 50 to 60 mm, it has a greater quality and can clearly show the moon's craters, Saturn rings, Jupiter's belt and other galaxies. With larger apertures of about 100 mm, it shows fainter objects but with finer details compared to smaller apertures.

The eyepiece is the most important part of the telescope and binoculars. The eyepiece should have a good quality and can be changed depending on the magnification you require.

With a wide variety of telescopes available, here are some simple steps before considering what is best suited for your requirement:

• Make sure to check the tube by looking through the main lens. Look for the stop with a disk having a very small hole. The stop is used in trying to make the object look sharper. It is similar to the f-stop used in cameras. Be reminded that this will definitely reduce effectiveness of the aperture and in effect, the image brightness is sacrificed.

• Try the telescope outside and use it to observe the moon. It is recommended to do this during nighttime. The edge of the moon should be sharp and should not have any false color. Use it outdoors and not inside the house or through the window.

If the telescope does not meet the above-mentioned tests, never purchase it; otherwise it will not perform as you expect it to be and of course, buying it is a waste of money.

One of the most significant qualities in choosing your telescope is the magnification. The magnification depends on the type of the eyepiece. Telescopes come in a variety of eyepieces, for low, medium and high.

These telescopes have f-numbers just like the cameras. The total length of the telescope is the same length of the light path starting from the main lens going to the eyepiece.

Telescope functioning

Aperture Dimmest star Greatest

(millimetres) (inches) (magnitude) usable power

150 6.0 13.6 300

100 4.0 12.7 200

80 3.1 12.2 160

60 2.4 11.6 120

Mounting is also an important consideration in proper positioning during observation. Altazimuth design is a simple type of mounting and is usually used for small refractors.

As with the larger telescopes, equatorial mount is used. This type of mounting has to be set up with polar axis pointing to the north celestial pole. This type of mounting is a lot more expensive but is more effective in maintaining the view, such as when the Earth is turning on its axis.

Several years ago, Dobsonian mount had become the most popular because it is less expensive and portable. It is an alternative mounting as a replacement for the equatorials.

With so many beautiful views of the galaxy, it is therefore important to have the best binoculars and telescope. With a good telescope, you can appreciate more the beauty of the universe beyond the reach of the naked eyes.