Binoculars with a strength of 7 X 35 can actually be a better choice than a telescope. Binoculars are more portable and convenient, relatively inexpensive, and it's wiser to get cheap binoculars over a cheap telescope. With the 7 X 35 binoculars, the first number stands for the eyepiece magnification and the second number is the aperture in millimeters. Binoculars of this caliber are lighter and easy to hold.
There are three types of telescopes available for beginning astronomers.
The most readily recognized type of telescope is the refractor, which has two lenses at the ends of its tube. It is important to avoid department store cheap models, as these quote large magnifications while having useless small apertures. Telescopes are made to collect light, not magnify images. Normal terrestrial telescopes have extra lenses to keep an image right side up, but this extra lense is left out of astronomical telescopes because it reduces light. Without a filter on the lens, rainbow tints can be seen around bright objects like planets. This is called chromatic aberration. Refractors can cost more than other types of telescopes, but, being smaller, these make great instruments for beginners.
Next is the reflector telescope, and in this type, light travels down the tube and reflects off mirrors before leaving through an eyepiece. The reflector does not have chromatic abberation, and needs to be larger than a refractor in order to be as equally effective. Reflectors are the most comfortable telescope usually because of the eyepiece position, but the main mirror may need to be adjusted frequently. Luckily, there are kits to help with this problem. The most popular type of reflector is the Dobsonian, which has a mount close to the ground instead of a tripod, keeping you from kneeling and possessing an elastic neck to look upwards.
The third type of telescope is the Schmidt-Cassegrain. This uses lenses and mirrors to fold the light path back on itself within a compact tube. They are generally cheaper than refractors, but dearer than reflectors. They are more portable and easier to handle than the other two.
Sometimes telescope specifications quote numbers which will not affect the image you see. However, they can affect the exposure you need if you start into astrophotography. It is wise to get familiar with your telescope and the sky before you look into astrophotography though.
By joining a local astonomy club or checking a library, you can evaluate different types of instruments. Also, astronomy magazines have reviews as well as advertising for good telescopes.
Although you should buy the biggest aperture you can afford, don't get a large telescope if you will have to carry it a long way. A smaller telescope would be easier to set up and therefore more likely to be used. You will also be wasting your money on a large telescope if light pollution and atmospheric turbulence in your area are high, as you won't be getting the best from the instrument.
It's best to spend most of your money on a buying a large aperture instead of telescope accessories. Doubling the aperture number will calculate the maximal practical magnification: i.e., a 70mm aperture will have a maximum magnification of 140x. Do not buy an eyepiece that is stated to stretch magnification past maximum aperture value. Start simple with eyepiece choices, such as a Kellner, which is a good all around eyepiece. If you place a Barlow lens between an eyepiece and focuser, magnification can be tripled.
A telescope also magnifies the movement of objects across the sky and the instrument will have to be moved repeatedly to keep the object in the field of view. To cope with this different mounts and drives have been devised that enable the telescope to follow the moving object. You can get electronic drives to point the telescope, but the most important thing is that the mount is sturdy.
It is important to realize that many textbook and telescope advertisement photos are long exposures with false colors added. Stars seen through a telescope will always look like points of light, and you will not see color in dim objects. The eye is not sensitive enough.
So what can you expect to see with a beginners telescope? A 3-inch (75mm) refractor or 6-inch (150mm) reflector will allow you to see many galaxies and nebulae, Saturn's rings, Jupiter's largest moons and hundreds of craters on the moon. Plenty of wonderful objects to serve as an introduction to the night sky.
There are three types of telescopes available for beginning astronomers.
The most readily recognized type of telescope is the refractor, which has two lenses at the ends of its tube. It is important to avoid department store cheap models, as these quote large magnifications while having useless small apertures. Telescopes are made to collect light, not magnify images. Normal terrestrial telescopes have extra lenses to keep an image right side up, but this extra lense is left out of astronomical telescopes because it reduces light. Without a filter on the lens, rainbow tints can be seen around bright objects like planets. This is called chromatic aberration. Refractors can cost more than other types of telescopes, but, being smaller, these make great instruments for beginners.
Next is the reflector telescope, and in this type, light travels down the tube and reflects off mirrors before leaving through an eyepiece. The reflector does not have chromatic abberation, and needs to be larger than a refractor in order to be as equally effective. Reflectors are the most comfortable telescope usually because of the eyepiece position, but the main mirror may need to be adjusted frequently. Luckily, there are kits to help with this problem. The most popular type of reflector is the Dobsonian, which has a mount close to the ground instead of a tripod, keeping you from kneeling and possessing an elastic neck to look upwards.
The third type of telescope is the Schmidt-Cassegrain. This uses lenses and mirrors to fold the light path back on itself within a compact tube. They are generally cheaper than refractors, but dearer than reflectors. They are more portable and easier to handle than the other two.
Sometimes telescope specifications quote numbers which will not affect the image you see. However, they can affect the exposure you need if you start into astrophotography. It is wise to get familiar with your telescope and the sky before you look into astrophotography though.
By joining a local astonomy club or checking a library, you can evaluate different types of instruments. Also, astronomy magazines have reviews as well as advertising for good telescopes.
Although you should buy the biggest aperture you can afford, don't get a large telescope if you will have to carry it a long way. A smaller telescope would be easier to set up and therefore more likely to be used. You will also be wasting your money on a large telescope if light pollution and atmospheric turbulence in your area are high, as you won't be getting the best from the instrument.
It's best to spend most of your money on a buying a large aperture instead of telescope accessories. Doubling the aperture number will calculate the maximal practical magnification: i.e., a 70mm aperture will have a maximum magnification of 140x. Do not buy an eyepiece that is stated to stretch magnification past maximum aperture value. Start simple with eyepiece choices, such as a Kellner, which is a good all around eyepiece. If you place a Barlow lens between an eyepiece and focuser, magnification can be tripled.
A telescope also magnifies the movement of objects across the sky and the instrument will have to be moved repeatedly to keep the object in the field of view. To cope with this different mounts and drives have been devised that enable the telescope to follow the moving object. You can get electronic drives to point the telescope, but the most important thing is that the mount is sturdy.
It is important to realize that many textbook and telescope advertisement photos are long exposures with false colors added. Stars seen through a telescope will always look like points of light, and you will not see color in dim objects. The eye is not sensitive enough.
So what can you expect to see with a beginners telescope? A 3-inch (75mm) refractor or 6-inch (150mm) reflector will allow you to see many galaxies and nebulae, Saturn's rings, Jupiter's largest moons and hundreds of craters on the moon. Plenty of wonderful objects to serve as an introduction to the night sky.
About the Author:
David Wildash shares information and tips on his website about Telescopes , and you can read more about buying a telescope
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