Choosing your first telescope, especially if you’re a beginner can easily become a harsh and demanding task when confronted by a bewildering variety of choices and their unfamiliar features. From cheap department store telescopes to computerized models and specialized apochromatic refractors, what’s the ideal way to pick the best telescope for beginners, and be able to enjoy it for years without spending a fortune?
When it comes to buying an equipment like a telescope, you would want to do your research and make sure to purchase something worth putting your money in. Perhaps you want to get started with astrophotography, and therefore need a telescope best for astrophotography specifically. Hopefully this post should ease your research on choosing the right telescope. Planned correctly, you pick a high-quality telescope that can last a lifetime.
A telescope has two essential features: high-quality optics and a steady, smoothly working mount. All other factors being equal, big scopes show more and are easier to use than small ones, as we’ll see below. Still, you should not overlook portability and convenience — the best scope for you is the one you’d actually want to use.
Types of Telescopes
Having gained a lot of popularity in recent times, there’s an infinite variety of telescopes from the ads in the astronomical press. Yet for all their varied shapes and sizes, there are 3 different types of telescopes of note for serious beginners and intermediate astronomers: Refractors, Newtonians, and Catadioptrics.
Refractors refract light through a series of glass lenses. A refractor is the stereotype of how a telescope is supposed to look — a long, gleaming tube with a large lens in front and an eyepiece at the back. The front lens (the objective) focuses light to form an image in the back. The eyepiece is a little magnifying glass with which you look at the image.
These Galileo type telescopes range from department store specials up to lakhs for advanced and custom-made instruments. Refractors are good for casually viewing the moon and bright neighbour planets like Jupiter and Saturn, as well as larger deep sky objects like the Orion Nebula and the Andromeda Galaxy.
The limitation to low priced refractors is Chromatic Aberration. You can think of this simply as blurring or colour fringing of objects. This phenomenon occurs because of different frequencies of light that don’t refract exactly the same. Remember the fraction of sunlight passing through a prism forming a rainbow effect? The same happens when light refracts through lenses of a telescope. This is more pronounced with bright objects like the moon and planets, but not with dimmer stars. As prices of refractors go up, it’s primarily attributable to aperture (the diameter of primary lens) and the optics to reduce the Chromatic Aberration. You can specifically buy refractors called Apochromatics, or APOs that have effectively no chromatic aberration and are amazing for wide-field astrophotography, but again the prices for these scopes start at approximately Rs 14,000.
It is good for beginners and general purpose use.
Delivers wide field views
Above about 100mm, its cost per inch of aperture becomes really high.
It is prone to chromatic aberration
Buying range should be between $100-200 (Rs 7,000 to Rs 14,000).
Watch out for poor optical quality and cheap scopes.
#2 Newtonian Reflectors
The second type of telescope, the reflector, uses a mirror to gather and focus light. Many may call this type the best telescope for beginners, since Newtonian telescopes use one large primary mirror instead of number of lenses. Its most common form is the Newtonian reflector (invented by Isaac Newton), with a specially curved concave (dish-shaped) primary mirror in the bottom end of the telescope. Near the top of a small, diagonal secondary mirror directs the light from the primary to the side of the tube, where it was met by a conveniently placed eyepiece.
The mirror at the back of the scope reflects and focuses the light back up towards the top. Here, it reflects again off an angled secondary mirror and out to the eyepiece on the side of the telescope body. The Hubble, a variation of a Newtonian reflector, is one of the most professional instruments today. Typically a Newtonian uses a german equatorial mount to balance the weights of the telescope tube with a counterweight. This makes Newtonians a little more complex to operate for the beginner.
It gives best value per inch of aperture.
It is excellent for visual observing of planets and deep space objects.
It is not well suited to astrophotography, except for short exposure planetary imaging.
It has bulky tubes and bases can be difficult to transport and store.
Correct Price Range to buy:
Should be bought under $300 (Rs 20,000).
#3 Schmidt-Cassegrains or Catadioptric
Then there’s the third type of telescope, the catadioptric or compound telescope. Invented in the 1930s, the aim was to marry the best characteristics of refractors and reflectors: they involve both lenses and mirrors to form an image. Schmidt-Cassegrains Telescope (SCT) has a very short Newtonian with a large lens at the front and the objective pointing straight out the back, making it look like a short, fat refractor. The upshot is that you can obtain a large-aperture, long-focus telescope that’s very transportable.
SCTs are ideally suited for planetary observing and some of the smaller deep space objects. They are also a great scope for planetary photography. SCTs are the most compact and lightweight scopes at larger apertures, but they are notably more expensive than Newtonians.
It delivers better value per inch of aperture than refractors above 100mm.
Great for planets and planetary astrophotography.
It has the smallest physical size for the largest aperture.
It is significantly expensive than Reflectors/Refractors telescopes for the same aperture.
Correct Price Range to buy:
Should be purchased under $10,000 (Rs 2.5 lakhs).
It has generally narrower field of view than other types of scopes.
This covers the essentials of what you need to know before you buy the best telescope for beginners. One aspect to remember – any telescope has the power to give you eyes for a universe of celestial delights. With a little care in choosing the best telescope, beginners will be ready for a lifetime of ecstasy in exploring the cosmos.