Astronomy

If you have ever looked up in wonder at the starry night sky and wished for close up views of faraway sights, then explore our 'Astronomy Shop' because we will have a telescope for you. Everything from hand-held beginner telescopes to large diameter reflecting telescopes designed for majestic views of the heavens.

Before you buy a telescope, two important questions need to be asked.

• Who is going to be using the telescope?
• What is the primary use going to be?
• Types of telescopes
• Factors to consider

furthermore you will need to consider...

Which type of telescope is going to suit your needs... there are many to choose from depending on your purpose and need for the telescope! We have included a list of important factors that need to be considered when finalising your choice. 

 Who is going to be using the telescope?

If the telescope is to be used by children or beginning users, then a lightweight, hand held unit may be for you.

If the telescope you wish to purchase is for the whole family, then perhaps a combination telescope for land and sky use will suit your needs.

Tasco has telescopes for every age group: from young children just starting to explore the world we live in to advanced models that open the entire universe to wondering eyes.

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What is the primary use going to be?

If you wish to observe objects on earth right-side up, then a terrestrial telescope is for you.

If land and sky viewing is desired, Tasco offers several combination telescopes.

Should you wish to use your telescope for astronomical purpose only, many models feature a large diameter lens and equatorial mounts. 

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Types of Telescopes

Astronomical

Intended for viewing celestial bodies and produces inverted images. Offers powerful magnification and must be mounted on stable tripod or pillar stand.

Terrestial

Designed for viewing land objects and produces erected or "right side up" images. Moderately powered scopes are hand held, more powerful scopes are mounted on tripods.

Combination

Astronomical telescopes which present inverted images, with a special optical accessory (erecting eyepiece), quickly converts to terrestrial telescopes.

Refractor

Telescope using an objective lens through which light passes.

Reflector (or mirror)

Telescope using a concave mirror as its objective.

Photo Adapter Tube

A mechanical unit which when used in conjunction with a T-mount, allows a telescope to become a telephoto lens for a camera.

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Factors to Consider

Power - What It Means

When people think of telescopes, they often wonder about the "power", and what it means. Power, or magnification, is defined as how many times closer an object appears through the eyepiece as opposed to viewing the same object with the naked eye.

Tasco telescopes have plenty of power for use when you need it. Some units allow you to increase or decrease power by simply rotating a single control. Other telescopes have interchangeable eyepieces which allow you to vary the magnification.

The diameter, or size, of the objective lens effects how close and clear you can see objects through the telescope. Tasco telescopes come with lenses ranging from 30mm hand held units all the way to 125mm mirrors, which is a feature on the model 8V reflector

Eyepieces

The eyepiece is the part of the telescope that you look into. It is also the main component that controls magnification or power.

To determine power, simply divide the focal length of the eyepiece (usually printed on the top or side of the eyepiece) by the focal length of the objective lens (usually printed on the nameplate label).

If your telescope has an objective focal length of 700mm and you are using a 20mm eyepiece, divide 20mm into 700mm and you will reach the number 35, or 35 times closer. If you were using 100 power and looking at an object 700 feet away, the object would appear to be 7 feet away when viewed through the eyepiece of your telescope

Coating

Modern telescope have something that early astronomers never had: the coated lens.

The coatings used today actually increase the amount of light that passes through the lens, giving you brighter and clearer views than ever before

Focusing Systems

Tasco telescopes have three types of focusing assemblies available.

The simple push/pull or twist focusing assembly is featured on beginner and hand held units. The rack and pinion systems are a feature on the more advanced models.

Rack and pinion types have focus tubes with "racks" or teeth, mounted on the bottom, and a focus wheel containing a pinion gear. By rotating the focusing wheel, exact and precise views can be obtained by anyone, young and old alike. The third type, helical screw, used on most zoom models provides compact design, yet retains precise focusing control.

Refractor VS. Reflector

Refracting telescopes consist of an objective lens in front and the eyepiece, or the lens you actually look through, at the rear. The light passes through at the rear of the objective lens.
As light passes through the objective it is bent, or refracted into a cone, which ends at the focal point. The eyepiece magnifies this "point" producing an image for the eye too see.

Reflecting telescopes use a mirror as the objective, reflecting light forward to the secondary mirror, which redirects the light to the side of the telescope where it is focused and then magnified by an eyepiece.

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