28Feb2017

What Can You See in a Telescope?

Nothing can compare with the feeling of making a direct connection to the cosmos!  This is what a telescope can bring. 

Seeing for yourself the distant worlds of our solar system, ephemeral comets drifting through space, far-flung clumps of stars, and the ghostly glow of galaxies deep in the void, is a deep personal experience like no other.

A telescope is a subtle space ship of the mind.  The views will not look like the full color spreads in magazines and books. Such photographs need long exposures of many minutes or even hours.  The human eye does not take time exposures.  It cannot perceive colors in dim light.  What the eye can do is see very fine detail in structure and contrast.  Your telescope’s range is limited only by your willingness to be patient, to learn how to use it to its best advantage, and to learn how to really see what it is showing you.

The Moon will be dazzlingly bright and sharp with a lifetime of detail to explore.  The planets will look very small, even with high power.  But if you take the time for a good long look, you’ll be surprised how much color and subtle detail will be revealed, especially during brief moments when our atmosphere is steady.  Saturn’s rings and Jupiter’s bands are always showstoppers.

The Moon and planets make rewarding targets from even the most light-polluted places. Stars are tiny and sometimes colorful pinpoints of light, no matter how big a telescope you have.  Star clusters range from large, loose groupings of brilliant celestial jewels to faint and far away smudges of light at the limits of vision.  Nebulae and galaxies run the gamut from big and bright to frustratingly faint.

Patience and persistence will reward you with delicate detail in structure and contrast.  The best views of nebulae and galaxies are from dark sky locations where there is little light pollution.  A little knowledge of your target’s place in the grand scheme of the universe can make its observation a more meaningful one.

All of your observing, with the unaided eye, binoculars or a telescope, will be easier and richer with the help of a good guide book, star maps and sky simulation software like Starry Night.

Binoculars are a Good Start

Binocs

If you already own binoculars, put them to work.  Be prepared for a pleasant surprise.  They are easy to aim and use, giving bright, wide-angle images that are upright and not reversed (as is often the case with a telescope).  Experienced amateur astronomers are never without binoculars, no matter what kind of telescope they might own.

Binoculars let you see Jupiter’s moons orbiting around the planet – it is like watching a miniature solar system in motion. They provide wonderful views of the blasted surface of Earth’s Moon.  Binoculars reveal the brighter star clusters and nebulae, too.  You can see bright sparks of stars shrouded in wisps of faint interstellar gases.  Others will appear as a faint glow of ghostly light.

The Milky Way will amaze you with its glowing star clouds and knots of dark nebulosity silhouetted against the brighter galactic carpet.  With your binoculars you can enjoy countless hours of travel in the stellar realms of the night sky. *  For a detailed run down on buying and using binoculars see our article HERE

Six Things To Know About How To Buy a Telescope

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Power – A good telescope will not talk about its “Power”: If the box blares “300X” or other numbers about the “Power” the telescope within has, Caution! High power sounds great, but, there’s a catch. While high magnification makes an object appear larger, light gathered by the scope is spread over a larger area creating a fainter image. Also, “high-powered” telescopes have restrictions of the eyepiece design, which may limit how much of the large image you can actually see. Sometimes, lower power provides a better viewing experience.

Refractor/Reflector – Advantages and disadvantages to each type: A refractor telescope uses two lenses. At one end, is the larger lens, called the objective. On the other end is the lens you look through, called the ocular or eyepiece. A reflecting telescope works a bit differently. Light is gathered at the bottom of the telescope by a concave mirror, called the Primary, which has a parabolic shape. There are many ways the primary can focus the light, and how it is done determines the type of reflecting scope.

Aperture – Aperture size is the true key to the “power” of a telescope: The aperture of a telescope refers to the diameter of either the objective lens of a refractor or objective mirror of a reflector. The aperture size is the true key to the “power” of a telescope. Its ability to gather light is directly proportional to the size of its aperture and the more light a telescope can gather, the better the image you will see.

OK, so you’re thinking, “I’ll just buy the biggest telescope I can afford.” Unless you can afford to invest in your own observatory as well, don’t go too big. A small telescope you can transport will probably see a lot more use than a larger one you don’t feel like hauling around.

Typically, a 70 mm refractor is a good choice – better still, 114 mm (4.5 inch) and 150 mm (6 inch) reflectors are popular for most amateurs. As you increase in size, reflectors become cheaper than refractors.

Focal Ratio – Know a Telescope’s Focal Ratio: The focal ratio of a telescope is calculated by dividing aperture size into its focal length. The focal length is measured from the main lens (or mirror) to where the light converges to focus. While a higher focal ratio does not always mean a higher quality image, it often means as good an image for similar cost. However, a higher focal ratio with the same size aperture means a longer telescope, which can translate into transportation woes.

Mount – Necessary for steady viewing: It’s likely you never even considered a mount when you thought of buying a telescope. Most people don’t. However, the mount is a very important part of a telescope. Some kind of stand to hold the telescope steady is essential. It is extremely difficult, if not impossible, to view a distant object if the telescope is not very steady. Most people do not have that steady of a grip.

There are basically 2 types of mounts, altazimuth & equatorial. Altazimuth is similar to a camera tripod. It allows the telescope to move up and down (altitude) and back and forth (azimuth). The equatorial is designed to follow the movement of objects in the sky. Higher end equatorials come with a motor drive to follow the rotation of the Earth, keeping an object in your field of view longer.

Eyepieces – Power is not the object: Your new scope should have at least 1 eyepiece, and often 2 or 3. An eyepiece is rated by millimetres (mm), with smaller numbers indicating higher magnification. A 25 mm and 12 mm eyepiece is common and appropriate for most beginners. You can easily buy more quality eyepieces as needed.

Earlier, discussing power, I said a telescope’s power or magnification is not the best indicator of a good telescope. As with the whole, so the parts. A higher power eyepiece does not mean better viewing. Higher and lower power eyepieces each have their place in observing.

While a higher magnification eyepiece may provide more details, it may be harder to keep an object in view, unless you are using a motorised mount. They also require the telescope to gather more light to provide a clearer image. A lower power eyepiece makes it easier to find objects and keep them in view. Lower magnification eyepieces require less light, so viewing dimmer objects is easier.

Refractor Telescope Advantages and Disadvantages

http://i23.photobucket.com/albums/b395/JRWJR/JRWJR1/P9130516.jpgAfter initial alignment, refractor optics are more resistant to misalignment. The glass surfaces are sealed inside the tube and rarely need cleaning. The sealing also minimizes affects from air currents, providing steadier sharper images. Disadvantages include a number of possible aberrations of the lenses. Also, since lenses need edge supported, this limits the size of any refractor.

Reflector Telescope Advantages and Disadvantages

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Reflectors do not suffer from chromatic aberration. Mirrors are easier to build without defects than lenses, since only one side of a mirror is used. Also, because the support for a mirror is from the back, very large mirrors can be built, making larger scopes. The disadvantages include easiness of misalignment, need for frequent cleaning, and possible spherical aberration.

Price – Let the buyer beware. This is as true today as it ever has been in the past. It also applies to purchasing a telescope. Just as with any other product, it is almost always true that “you get what you pay for.”

Now, I’m not saying to go out and spend a lot of money on a telescope. The truth is that most people do not need an expensive telescope. Still, though, I do recommend that you buy the best telescope you can afford for the type of observing you plan to do. NEVER buy a telescope from a department store – always buy from a reputable dealer or camera specialist…like us!  Go HERE.

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