Why buy a Galileo telescope?

Telescopes by Galileo are produced with the beginner to intermediate sky watcher in mind. By addressing and correcting the three areas below, users will not be frustrated when using their Galileo telescopes for the first time.

Assembling Telescopes

Telescopes are inherently difficult to setup. One prime example is while you are attaching the tripod legs to the yoke mount of the telescope. With most telescopes you must have a great deal of patience for this step. "The Galileo Difference" is: All Galileo telescopes include pre-assembled, metal tripods ready to go right out of the box. They have made this step so simple. Just extend the legs and adjust the retractable rubber feet and your tripod is ready to use. Additionally, the Tripod is extremely sturdy and provides maximum stability for the telescope. Because the tripod must hold the telescope without movement, it is a critical part of the scope.

Locating Objects with Telescopes

Telescopes usually include only a standard finderscope for locating objects. Unfortunately these low powered finderscopes are inefficient and difficult to use.

"The Galileo Difference" is: Galileo’s MARS EYE ELECTRONIC FINDERSCOPE, found on all Galileo telescopes, puts you behind the telescope, seeing what the telescope sees, thus eliminating the frustration of the typical finder scope. Additionally, all Galileo telescopes include the Galileo Planetarium computer program. With the Planetarium you will be able to locate any object in the sky the first night with your telescope.

Land Viewing with Telescopes

Most beginners do not know telescopes produce an image that appears up side down when viewing land objects. This is because another lens is required to correct the up side down image in telescopes which restricts the amount of light the telescope can bring in. "The Galileo Difference" is Telescopes by Galileo can easily be adapted for land viewing because most of our telescopes include an erecting lens or prism enabling the telescope to be used for land viewing.

The Galileo Difference

Telescopes by Galileo are designed to be affordable and are endorsed by Astronomical Societies. We work closely with ALPO (The Association of Lunar and Planetary Observers) who offers the experience and knowledge to help the beginning astronomer learn and enjoy their telescope. Galileo's purpose is providing the absolute best value in optical products. Experience “The Galileo Difference.”

Selecting and buying the right telescope really boils down to your budget, what you plan on spending the most time viewing, and where you will using your telescope most. With that said, here are some guidelines:

Sound Advice When Choosing Your Telescope
·         First telescope and on a budget? Buy a Dobsonian reflector.
·         Interested mostly in viewing planets? Buy a refractor.
·         Interested in viewing galaxies, nebula, and star clusters? Buy the biggest reflector you can afford - this will be a Dobsonian.

See these short clips on the difference between refractor and reflector telescopes on YouTube. 

Do's for Buying Telescopes

• As a first telescope, a 6" or 8" Dobsonian reflector offers great bang for the buck. On the refractor side, an 80mm on a stable mount is also an OK alternative first telescope.
• Plan on spending a minimum of $300 for a decent beginner's telescope.
• Get an oversized/overrated mount - telescope mounts MUST be sturdy.
• Stick with 1.25" size eyepieces at a minimum, stay away from 0.965" designs.
• Get a size and weight that you don't mind setting up or lugging around to remote sites.
• Select 2 (or 3) quality eyepieces and a Barlow lens. Low-cost but acceptable-quality eyepieces include Kellners and Plössls.

Don'ts for Buying Telescopes

• Don't buy a telescope from a department store, nature-science store or toy store. These are totally unsuited for astronomy and will end up unused or in the trash.
• Avoid getting so large and heavy of a telescope that you don't want to use or transport it around.

One More Word of Advice
Low-quality telescopes serve more to stifle the interests of a beginning amateur astronomer than stimulate them. Buy the largest aperture (diameter) telescope within your budget. It is aperture, not power, that determines what you will actually see through the telescope. If you feel that your interests will continue, consider purchasing a more advanced scope with an aperture of 90mm or higher.

Q: What are the different types of telescopes?
A: There are three optical classes of telescopes: Refracting, Reflecting and Catadioptric

Q: What is a Reflector Telescope?
A:  The reflector uses a concave mirror that is placed in the back of the tube. The concave mirror reflects the light back to a much smaller mirror that is placed in the middle or front of the telescope. The little mirror then reflects the light to an eyepiece which in turn allows you to observe the universe. As a reflector utilizes a small mirror that is placed in the middle of the telescope it is said that the reflector performs not as well as the refractor because a small part of the light is blocked.

Q: What are the advantages and disadvantages of a Reflector Telescope?
A: Advantages: Reflector telescopes cost less to produce than other types of telescopes thereby offering the most telescope for the money. Reflector telescopes produce good images and are favored by astronomers who need the largest possible telescope to find distant, faint objects beyond our solar system (deep-sky objects).
A: Disadvantages: Reflector Telescopes are more fragile than other types of telescopes and need periodic readjustment of the telescope mirrors (a process called collimation) and, because they are open on the top (Newtonian reflector), the mirrors are exposed to dust and dirt and therefore need periodic cleaning.
The reflector telescope is by no means fragile, but it is the least childproof telescope design.
When thinking of children's use, remember the reflector telescopes eyepiece is located at the top of the telescope which may make it more difficult for children to reach.

Q: What is a refractor telescope?
A: Refractor telescopes use lenses (not mirrors) at the top of the telescope to focus light rays into an eyepiece at the bottom of the telescope. It is the same design used in binoculars and most spotting scopes (daytime telescopes). See our Spotting Scopes are for Spotting Scope Selections
The refractor uses a lens that is placed in the front of the tube. The light passes through the lens and is deflected to a focal point where the image is formed.
The lens telescope is a simple, sound and optical (almost) perfect instrument.

Q: What are the advantages and disadvantages of refractor telescopes?
A: Advantages: One especially nice advantage of a refractor telescope is that they are virtually maintenance free since the telescope tube is closed (not open as in a Newtonian reflector) and there is no telescope mirror to adjust.
The refractor telescope is the most rugged telescope design and in the most expensive versions, a refractor will produce the brightest and sharpest image per inch of telescope. When thinking of children the refractor telescope is a good choice. It is not only rugged, but the refractor telescopes eyepiece is located at the bottom of the telescope where it easier for them to reach.
Refractor telescopes are also easier to use as a daytime telescopes (with an image erector) than reflector telescopes.
A: Disadvantages: The refractor telescope is the most expensive telescopes per inch of telescope size; beyond three inches, the refractor goes up very quickly in price. If you buy a beginner a small refractor, be advised that the beginner may quickly outgrow it if they stay with astronomy for long.

Q: What is a catadioptric telescope?
A: Catadioptric (mirror-lens) telescopes, characterized by short, highly portable optical tubes, use both mirrors and lenses. Light is reflected from the front to the back through three mirrors, with the light projecting out the rear of the scope to an eyepiece. Catadioptric telescopes are the ideal all-around telescopes for terrestrial and astronomical observation.

Q: What is a Dobsonian telescope?
A: A Dobsonian telescope is more of a type of mount than a type of telescope. A Dobsonian telescope is a large Newtonian reflector, six inches or larger, mounted on a simple box-like alt-az mount.

Q: What are the advantages and disadvantages of Dobsonian telescopes?
A: Advantages: A Dobsonian telescope is the essence of simplicity and a perfect choice for the astronomer who shuns hi-tech gadgetry and electronics. The "Dob" is the telescope for the deep-sky purist who wants to see the faintest objects at millions of light years beyond our solar system. The secret of the Dobsonian telescope is in its size - it is the largest telescope for the money you can buy. A huge ten inch, or even twelve inch Dobsonian telescope will cost less than a fancy computerized telescope half its size and will easily take you to places in the universe no smaller telescope can go. Even advanced amateur or a beginner will not outgrow a ten inch Dobsonian in his or her lifetime.
A: Disadvantages:  Dobsonian telescopes above ten inches in size are a problem to transport - a disassembled ten inch Dobsonian telescope will still squeeze into a hatchback with all seats folded down and no passengers, but a twelve inch Dobsonian will not. Because a Dobsonian mount is all manual, it requires constant readjusting (though easily done with practice) to keep an object in the telescope eyepiece. For the same reason, it is limited for use as an astrophotography telescope.

Q: Why is a telescope mount important?
A: A telescope is only as useful as its mount - the higher the magnification, the truer this becomes. A telescope mount not only steadies the telescope, it also allows the telescope to follow stars and planets as they move across the night sky. When seen in the eyepiece of a telescope, stars and planets move slowly across the field of view in the eyepiece and disappear (because the telescope magnifies the earth's rotation, not because the stars move). To keep the object centered in the eyepiece, the telescope must be moved constantly. This is done in a number of ways, depending on the telescope mount.

Q: What is an Alt-AZ telescope mount?
A: An alt-az telescope mount requires you to move the telescope to the object you wish to find. You then move the telescope in two directions - up-down and right-left - to keep the object centered in the eyepiece as it moves. This is because stars move across the sky in a gentle arc or curve, but an alt-az telescope mount only allows the telescope to be moved in a straight line.

Q: What are the advantages and disadvantages of an alt-az telescope mount?
A: Advantages: Alt-az telescope mounts, because of their simplicity, are the least expensive of all telescope mounts. They are uncomplicated and rugged and the least likely to be damaged by over-eager children.
A: Disadvantages: Because a star or planet follows a gentle curve across the night sky instead of a straight line, a telescope on an alt-az mount must be adjusted both in an up-down as well as a right-left direction to keep a star or planet in the eyepiece. This is not much of a problem at low magnifications, but above 75x or so, an alt-az mount can be frustrating for a beginner to use.

Q: What is an equatorial mount?
A: Although celestial objects are essentially fixed in their positions, they appear to move in an arc across the sky. An equatorial mount compensates for the earth's rotation and allows the observer to track the moon, planets and stars. By aligning one axis of the equatorial mount to the earth's rotational axis, the observer can track objects by turning just one control cable.

Q: What is a motorized mount telescope mount?
A: A motorized telescope mount is a mount that requires you to move the telescope to the object you wish to see, but then keeps it in the eyepiece for you by moving the telescope with a motor. In other words, once an object is found, no adjustment is needed to keep it in the eyepiece. A motorized telescope mount can be any type of mount - alt-az, fork, or equatorial- that has an attached motor. The motor moves the telescope at the same rate of speed as objects that move across the night sky.

Q: What are the advantages and disadvantages of a motorized telescope mount?
A: Advantages: For visual observing, a motorized telescope mount makes it much easier to use high magnification - the observer spends more time viewing and less time moving the telescope. This is also the best telescope mount to use when sharing the telescope with others - no need to adjust the telescope after each person has had their turn. For serious astrophotography, a quality motorized mount is a must, with a motorized equatorial preferred.
A: Disadvantages: In order to be effective, a motorized telescope mount must be carefully aligned first. The procedure will vary with type of motorized mount, and periodic corrections will be needed to keep things in alignment. The best motorized equatorial mounts can also be very expensive and cost as much or more than the telescope.

Q: Which is more important: power or aperture?
A: Power, or magnification, is one of the least important factors of a telescope. The key to observing fine detail is aperture - which is the diameter of the telescope's main objective lens or primary mirror. The power at which a telescope operates is determined by the eyepiece used. Power is useful, but a common mistake of a beginner is to overpower the telescope to magnifications that the aperture and typical atmospheric conditions cannot support. The result is a fuzzy image with poor resolution. An image viewed at a lower power is brighter with higher resolution.

Q: How do I calculate power?
A: Power is a function of the focal length of the telescope's main objective lens or primary mirror and the focal length of the eyepiece used. The focal length of the lens or mirror is found on the optical tube of the telescope while the focal length of each eyepiece is printed on the eyepiece. To calculate power, divide the focal length of the eyepiece into the focal length of the telescope's objective lens.
Example: A telescope with an objective lens focal length of 1000mm and a 25mm eyepiece yields a power 40x. i.e., 1000 divided by 25 = 40x.

Q: What does focal length mean?
A: Focal length is the distance (usually expressed in millimeters) from the telescope's main optical element (main lens or primary mirror) to the point where light rays are brought to a focus. Focal length is important because it determines the magnifying power of the telescope. Magnifying power is calculated by dividing the focal length of the eyepiece (printed on the barrel of the eyepiece) into the focal length of the telescope.

Q: What about the eyepiece?
A: The eyepiece used determines the magnifying power (i.e. 90x) of the telescope. Changing the eyepiece changes the power. Telescopes usually come with at least two eyepieces: one for low power and a second for a higher power view.

Q: Why is aperture (diameter) important?
A: A larger aperture (or diameter) telescope collects more light. The more light collected, the more detail you'll see. Although power is useful, it has no bearing on the level of detail. It is aperture that determines what you will see through a telescope.

Q: How much Aperture should I get?
A: Generally, you should buy as much aperture as you can reasonably afford. But for most observers, the following sizes will be more than sufficient:

• Refractors: 3 inches
• Reflectors: 4 to 8 inches
• Catadioptric telescopes: 6 to 8 inches

Q: What is a Barlow lens?
A: Inserted into the telescope in front of the eyepiece, the Barlow lens effectively multiplies the focal length of the main telescope.

Q: How can I center objects to track?
A: A viewfinder helps you find and center an object in the telescopic field. It is a small, low-power, wide-field telescope, usually equipped with internal crosshairs for easy object-sighting. The viewfinder is aligned parallel to the main telescope. Objects first located in the viewfinder are then also in the main telescope's field.

Q: The images I see through my telescope are upside down. Can I do anything to view them right side up?
A: Astronomical telescopes show objects upside down and reverse left for right. This is standard for astronomical viewing, but for land viewing most observers prefer images to be seen right side up. By using an erecting prism, you will see a correctly-oriented image.

Q: Can I track objects by moving a telescope up and down and from left to right?
A: Widely used in both land and astronomical viewing, a simple alt-azimuth mount allows a telescope to be moved vertically and horizontally to follow objects. Depending on the telescope, these movements can be made manually or electrically.

Q: What accessories do I need for a telescope?
A: Depending on what eyepieces your telescope comes with, you might want to add some extras. A low-power wide-field eyepiece (with a 40mm focal length) is good for land viewing or for scanning star fields, while a higher-powered eyepiece (with a 4mm to 9mm focal length), is ideal for viewing details of the moon and planets. A Barlow lens multiplies the power of an eyepiece. Camera adapters let you take photos of both terrestrial and astronomical objects. Other convenient accessories include cases, remotes, filters and tripods.