First time telescope buyer's guide

A question often asked on beginner forums or on reddit astronomy boards is, "What telescope should I get?" or "What is the best beginner telescope?" There's a helpful - if older - article from 2010 by Sky and Telescope that covers some (at the time) sub-$100 telescopes, all of which are more than that now by $10 to $30. That's a good place to start. But sometimes the budget is more (or less!). So what to do from there? There are SO many choice today, it's hard to know what to get. Here are some recommendations I think may help. First, watch these Telescope Basics videos. Even if the telescope is not for you, it will help you understand the types of telescopes and accessories, and what a user may be able to see more easily with one. It will only take half an hour or so. It's well worth the time to choose the best telescope. Second - and this is a recommendation hear a lot - consider binoculars. Or at minimum, leave some budget for a low-cost pair from Amazon (Celestron Cometron 7x50's price in 2020 when I updated this is around $37). I know, I know - astronomy screams "TELESCOPE!" and not binoculars, which seems to offhandedly remark, "Birding? Mountain-viewing? Neighbor-watching?" But if the gift is for YOU, and you want to learn the sky better, they really are helpful supplemental set of optics - they assist in familiarizing oneself with the night sky, finding objects up there, starhopping, and besides that, seasoned amateur astronomers ALWAYS use binoculars. They won't go unused, even after you get a telescope. But I know that's not the first thing on most people's minds. So... where to start if it absolutely must be a telescope - or if binoculars have already been purchased? Let's start with the low-end of the budget. Under $100 telescopes Consider some of the tabletop 76mm reflector Dobsonian type telescopes, such as offered by Celestron, Orion and some other brands. These are so much better than the 50mm refractors of yesteryear. They are solid, stable and provide far more light gathering than 50mm or 60mm refractors - that are often on wobbly tripods. One accessory you most likely MUST add? A barlow lens. The focal length on these is not long - usually around 300mm. That doesn't allow for a lot of magnification even with a 10mm eyepiece (just 30x). So a 3x barlow will get you up to 90x. That's suitable for planets, the Moon and double stars. $100 to $200 telescopes The Sky and Telescope article reviewed telescopes that fall into this category, but there are a couple more I think are worth considering in this price rance. One is the Orion Starblast 4.5, which is an adequately-sized aperture instrument that will gather decent light and show some good objects in the sky. The included eyepieces will net 26x and 75x, so low power and "useful enough for planets" medium magnification is at least included with the telescope. A 2x barlow wouldn't hurt, if there is another $40 or $50 available in the budget though. And functionally, this telescope is similar to the Funscope/Firstscope listed above, just a "bigger brother" version of it - a nice sturdy mount, wide field views, and adequate accessories included. Drawbacks include the short focal length, very fast focal length which will produce coma (this only affects the view near the edge of the field of view), and the three-element eyepieces included. But for the price, it is a very good value in my opinion. Note: I own an Orion Starblast 4.5, and it offers very good, wide-field views of many deep sky objects, and quite clearly in the center of the field. Overall, a good option. And consider building this simple-to-make, $40 tripod to help you with viewing. Since I wrote this article back in 2012, there are several other manufacturers that have similar telescopes. Do consider other manufacturers if you cannot find the Orion one. These are often made by the same Asian telescope manufacturers. On the flip side of that "fast focal length / coma aberration" coin is the Orion Starmax 90 Maksutov Cassegrain telescope. With a much longer focal length and a Mak-Cass design, the aberrations are practically non-existent, and the folded-optical path means a long focal length for higher-magnification viewing. Included eyepieces place the included magnifications at 50x and 125x - useful low-ish power, and a quite-usable higher magnification that is close to most night's limit on magnification of 150x anyway (regardless of telescope, due to atmospheric unsteadiness). Drawbacks are narrower field of view, which can make it harder to locate objects, a smaller aperture than the 4.5 scope, and a star diagonal that can be in an uncomfortably impossible position to view when the scope is pointed overhead at the zenith. And from the looks of it, the diagonal may hit the based before it can even be pointed overhead. But - zenith viewing can be difficult in some scopes anyway, and the recourse to this is... wait an hour or two for the object to rotate to a better position. It's a worthwhile option to consider. $200 to $300 telescopes I have no personal experience with this next telescope, but I have used the mount it comes on. The Celestron Astromaster 90 EQ Refractor appears to be a decent options. It's the first one I've mentioned that has that classic telescope "look": Long tube with the eyepiece at the end. That's partly why this is a qualified recommendation: The tube and scope, while of a focal length that will likely reduce chromatic aberration, is also long enough that it may cause that tripod to be unstable. Now, I have an Orion 90mm refractor the same length that I use on a Celestron mount that is exactly the same - BUT - I built my own tripod. My wood tripod is rock solid; I'm not so sure about the legs on that one. But a 90mm scope can show you a fair amount; I've seen the Crab Nebula (Messier 1) with my Orion (though barely), under my 4.5 magnitude skies. For about $20 more is the Orion version on their own mount (I built mine from various pieces). The Orion Astroview 90mm Equatorial Refractor is a telescope tube I own. The optics are certainly acceptable for an achromatic refractor of this focal length, nicely coated and exhibit only minor chromatic aberration. The focal length, surprisingly, provides not only nice high magnification views, but even decent wide field ones with a 32mm eyepiece. I do have a concern about the Orion tripod, as honestly, it looks a little flimsier than the Celestron - the Orion aluminum ones can be rather shaky and unstable. Note in the picture how the legs are not extened; that is probably the best way to use that, though it also means laying on the ground to view objects overhead - not ideal. One could fill the tripod legs with sand or put a 5 or 8 pound weight on the accessory tray to minimize vibrations, but in either the Celestron 90 or Orion 90's future, a wood new tripod would be the next best accessory to buy. $300 - $400 telescopes At this point, there really is one good option to recommend: An 6" Dobsonian reflector. A large aperture, solid mount, and great all-around performer, it is truly one of the "best bang for the buck" telescopes out there. These are largely made by the same couploe of Asian manufacturers, as with the telescopes listed above. So the optics are generally more than adequate, the differences tend to be in the accessories provides, such as finderscope, focuser and eyepiece(s). They all weigh about the same, and generally cost is in the same neighborhood from each other. For a little more, in the $450 to $550 range, this is where the "Get an 8" Dobsonian for a first telescope" comes into play. From my readings, either the Orion XT8, Zhumell Z8 Deluxe or Apertura AD8 are all worthy options. None are "premium" telescopes, but that are certainly perfectly adequate performers that can provide literally a lifetime of views, and for under $600, that's a pretty great deal if you ask me. Of course, collimation will really be required of these instruments, but that is a skill that can be learned. And Dobsonians, moreso than most other telescopes, are perfect contenders for adding upgrades and improvements. But these can be added over time. Out of the box, they are a great option, able to show both planetary and deep sky views that are of very good performance. If you can make this budget option, it's worth the investment. What I did NOT include - and why You'll notice I have not included any computer telescopes or very short refractors or a single Schmidt Cassegrain telescope. That is not because any of those options are bad, necessarily. But I do not believe that for the price points I have covered, that any of the options available are worth buying in the prices I have covered - anything worth getting costs more. (And if you DO have more to spend, by all means, consider some of the good options in the higher price ranges.) Others may argue that point about what to include in the prices I covered, and are welcome to that opinion. I just think the above options are some of the best options for beginners getting started, without having to worry about learning difficult to navigate computer modules with batteries that can run out or motors than can die, or telecopes that have aberrations that can really ruin the first-time user experience. Think about it: If your batteries die, or the computer breaks, or a motor malfunctions, what can you do with that telescopes? But if it is a manual telescope, you can ALWAYS use it - no batteries or technology needed other than a star map. Many of those other computerized / fancier / short refractor scopes may make great second options; but strongly consider the ones I have listed above as first-time instruments. And avoid the 60mm and 70mm refractors, if at all possible. I have several, and they can be fun to use... on the Moon, and a few (VERY few) bright targets. After that, they wind up collecting dust. Consider the options above, if the scope is to see substantial use beyond the excitement of the first few nights, and the budget is around $500 or less. Got questions? Email me! I appreciate the feedback, and may have even overlooked a good option. And also, I have absolutely no financial relationship with any of the companies I mentioned above, so I don't make any money from any of them, not matter from whom you buy. Writer : David Fuller is a long time amateur astronomer and builder of telescopes and observing items. His Eyes on the Sky YouTube channel has been helping people find "What's up?" in the night sky as well as understand how to use telescope and binoculars since 2010. He advocates for darker nights to not only see more in the cosmos, but for everyone to get better sleep and improve the nighttime environment overall. eyesonthesky com/articles/first-time-telescope-buyers-guide/

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Popular Science by Celestron StarSense Explorer 100AZ

Celestron has reinvented the manual telescope with StarSense Explorer—the first telescope that uses your smartphone to analyze the night sky and calculate its position in real-time. This special edition Popular Science by Celestron StarSense Explorer is ideal for beginners thanks to the app’s user-friendly interface and detailed tutorials. It’s like having your own personal tour guide of the night sky.

This video introduces the Celestron StarSense Explorer 100AZ telescope, which uses a smartphone app to guide users to celestial objects. The app aligns with the telescope and uses sky recognition technology to pinpoint its location, generating a list of visible objects. Users can then follow on-screen arrows to view their chosen object.

 

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Popular Science by Celestron StarSense Explorer 5" Schmidt Cassegrain

 

Celestron has reinvented the manual telescope with StarSense Explorer—the first telescope that uses your smartphone to analyze the night sky and calculate its position in real time. This special edition Popular Science by Celestron StarSense Explorer is ideal for beginners thanks to the app’s user-friendly interface and detailed tutorials. It’s like having your own personal tour guide of the night sky.

 

This video introduces the Celestron StarSense Explorer DX 5-inch SCT telescope, which uses a smartphone app to help users navigate the night sky. The app aligns with the telescope and uses sky recognition technology to pinpoint its exact position, then generates a list of visible celestial objects. Users can select an object and follow on-screen arrows to view it through the eyepiece.

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Celestron Astromaster EQ Series Telescepes

This video introduces the Celestron Astromaster telescope series, a great option for beginners. It highlights the ease of use and features of the telescopes, including the equatorial mount, Red Dot finder scope, and SkyPortal app. The video emphasizes the ability to observe celestial objects like the moon, Saturn, and Jupiter.

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মোবাইল ফোন এনেবল টেলিস্কোপ কেনার গুরুত্ব

 

যারা খুব সহজে মোবাইল এপের সাহায্যে টেলিস্কোপ দিয়ে আকাশ দেখতে চায়, তাদের উচিত Popular Science by Celestron StarSense Explorer 100AZ অথবা celestron starsense explorer dx 102az (102mm f/6.5 az refractor) টেলিস্কোপ কেনা ।

এধরনের টেলিস্কোপ দিয়ে আকাশ পর্যবেক্ষণ সহজতর হওয়ার পাশাপাশি আকাশের ছবি তোলাও সহজ হয়ে যাবে । উপরুন্তু দামও তুলনামূলকভাবে কম ।

 

 

শিপিং কস্ট ও টেক্স ছাড়া এর দাম ৩০০ মার্কিন ডলার । এটা backpackbang এবং সেন্ডকার্গো হতে কেনা সম্ভব । এসব প্রতিষ্ঠানের অফিস যথাক্রমে ঢাকার মহাখালী ও নিউমার্কেট ইস্টার্ন মল্লিকাতে । তাদের ফেসবুক পেজ ও ওয়েব সাইটের মাধ্যমেও যোগাযোগ করে কেনা যেতে পারে ।

 

 

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Why buy a reflector?

In a word – value. A Newtonian reflector offers more performance for your observing dollar than any other telescope type.
The reflector's large light-gathering area and relatively short focal length can provide bright images of deep space objects that are too faint for any small aperture refractor to see. And the reflector's large aperture can resolve details within those objects with a precision no small scope can match – if the seeing is good.

The penalty you pay for this performance is typically one of large size and weight – although not necessarily one of high cost, as reflectors traditionally cost the fewest dollars per inch of aperture of any telescope type.

The reason? A reflector has only one mirror to grind and polish to a precise curve (with an accuracy of +/-five one-millionths of an inch or better). A refractor, on the other hand, has two to four lenses, with a total of four to eight precisely curved surfaces to shape. And those lenses might have to be costly exotic glass formulations in order to provide satisfactory images. Similarly, a catadioptric scope has three or four curved optical elements to shape to a high degree of accuracy.

All that extra mirror and lens grinding and costly optical glass types in refractors and catadioptrics doesn't come cheap. That makes the one-curved-mirror and one-flat-mirror optics of a reflector the least expensive to make, and hence the lowest in cost per inch of aperture.

For the same amount of money, therefore, you get more aperture with a reflector than with any other scope type. And, all other things being equal, the bigger the aperture, the better the performance. An 8" reflector typically costs 50% less than a quality 4" refractor, and little more than 3.5" catadioptric, but will have four times the light grasp of either.

For purely visual deep space observing, Dobsonian reflectors are very cost effective. With huge mirrors (up to 24" in diameter) to gather light, and inexpensive wood mounts, these new Newtonians have brought about the age of the "light bucket" in amateur astronomy. The deep space observer on a budget has never had it so good.

The astrophotographer will also find that a large aperture equatorial mount reflector is excellent for recording deep space objects in detail, as well as visual observing. (Photography is not possible with an altazimuth Dobsonian reflector.)

The drawbacks of a reflector? There are five – diffraction, coma, size, weight, and added maintenance.

Light diffracted, or scattered, by a reflector's diagonal mirror can reduce image contrast in lunar and planetary observing, masking subtle surface details compared with an unobstructed refractor image. In addition, diffraction spikes on star images, due to the spider vanes that hold the diagonal mirror, can mask faint binary star components and smear globular cluster detail.

Because of the parabolic shape of their primary mirrors, all reflectors have coma – an optical defect in which stars appear triangular or wedge-shaped at the edge of the field. The faster the focal ratio, the smaller the coma-free field. This can be annoying in photos, where the entire field is available for leisurely inspection. It is usually unobjectionable visually, however, since objects of interest are normally kept in the center of the field, where eyes and eyepieces are sharpest and coma is less of a factor.

Since an 8" reflector can weigh up to 50% more than an 8" catadioptric, and its 48" long optical tube is not the easiest thing in the world to manage in an apartment elevator, a large reflector usually requires the elbow room afforded by a suburban environment. Also, since city light pollution almost invariably compromises deep space performance by washing out faint nebulas and galaxies, dark sky observing sites are always recommended with medium to large aperture reflectors. Large aperture reflectors (12"-16" and larger) almost invariably require a minivan or SUV for transport to the dark sky sites they need to avoid being overwhelmed by the effects of city and suburban light pollution. They often also need some friends to help you with the setup of the bulky components. Owning and using a large reflector is more of a lifestyle than it is a hobby.

In addition, unlike refractors or catadioptric telescopes, a reflector requires frequent recollimation or alignment of its optics, and its exposed mirrors mean that periodic cleaning will also be required. However, this maintenance typically averages only a few additional minutes of work per observing session.

These drawbacks aside, for serious visual observing of faint galaxies and nebulas, as well as for more-than-acceptable lunar and planetary observing, you'd be hard-pressed to equal, much less surpass, the excellent price-to-performance ratio of a Newtonian reflector. Reflectors have been a best-seller for over 300 years – and sheer value for the money is why.

REFLECTOR REPORT CARDS
(used in excellent seeing conditions and with no light pollution; adapted from Astronomy Magazine):

E = excellent; VG = very good; G = good; F = fair; P = poor.

Small aperture (3" to 6") reflectors:
Price range: $120-$1000
Portability: E
Ease of setup: VG
Ease of use: VG+
Performance on the Moon: E
Performance on comets: F
Performance on double stars: VG
Performance on galaxies and nebulas: F
Performance on planets: VG

Medium aperture (8" to 12.5") reflectors:
Price range: $400-$14,000
Portability: F
Ease of setup: F
Ease of use: VG+
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: VG
Performance on galaxies and nebulas: VG
Performance on planets: VG

Large aperture (13" and larger) reflectors:
Price range: $1200-$36,000
Portability: F
Ease of setup: P+
Ease of use: G+
Performance on the Moon: VG
Performance on comets: E
Performance on double stars: E
Performance on galaxies and nebulas: E
Performance on planets: E


Source:http://www.astronomics.com/main/category.asp/catalog_name/Astronomics/category_name/Why%20buy%20a%20reflector?/Page/1

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Why buy a refractor?

For serious lunar, planetary, globular cluster, and binary star observing – as well as for surprisingly good views of the brighter Messier, NGC, and IC catalog objects – many amateur astronomers prefer the crisp, high-contrast, diffraction-free images of a good refractor.
Under average seeing conditions, a useful rule of thumb in astronomy is that a good 3" to 4" refractor will usually outperform an average 6" to 8" reflector or Schmidt-Cassegrain for seeing details on the Moon and planets, splitting binary stars, and resolving globular clusters. The situation becomes a little more complicated when comparing refractors to Maksutov-Cassegrains or Maksutov-Newtonians, but (with a few high-priced exceptions) a good refractor will usually equal or outperform a Mak-Cass or Mak-Newt of equal or slightly larger aperture

Why? Unlike reflectors and catadioptrics (Schmidt-Cassegrains, Maksutov-Cassegrains, etc.), refractors do not have a secondary mirror obstruction or multiple-reflection optical path to introduce light-scattering diffraction and internal reflections that brighten the sky background, reduce contrast, and smear images.

Refractors also have the highest light transmission – the percentage of the light gathered by the scope that actually reaches your eye. Refractors can transmit 90% or more of the light they collect, compared with the 77% to 80% transmission of reflectors and 64% to 75% of catadioptrics. (The reflector and catadioptric percentages only concern mirror reflectivity. They do not take into account the light blocked by a reflector or catadioptric's diagonal or secondary mirror, which can reach a hefty 15% to 20% additional light loss in some scopes.)

Unlike reflectors and catadioptrics, which lose 1% to 1.5% of their reflectivity per mirror surface per year as their aluminum coatings gradually oxidize, the light transmission of a low maintenance refractor rarely deteriorates significantly with age. Century-old refractors are still used, and highly prized, by discerning amateurs, and the world's largest refractor – the Yerkes Observatory’s massive 40" – has been in constant professional use since 1897.

The result of a refractor's lower diffraction and higher light transmission? Given favorable seeing conditions, a modestly-sized refractor can show you subtle lunar and planetary features with a wider and more easily observed contrast range, and with more sharply etched detail, than is possible with the light-scattering optics of many larger reflectors and catadioptrics. This is especially true on nights of less-than-perfect seeing, when the details visible in a larger scope are often blurred by turbulence in our atmosphere. A smaller refractor looks through less of our unstable atmosphere and its images are consequently less affected by this turbulence. A good 80mm refractor, for example, can reveal more lunar detail than you can sketch in a lifetime of observing.

Diffraction spikes on a reflector's star images, caused by its diagonal mirror’s spider vanes, are absent in an unobstructed refractor. With no diffraction spikes to hide faint binary star components or smear globular clusters, refractors can resolve close-spaced stars more precisely than the typical reflector.

Since the Moon and planets are all brightly lit by the Sun, a large light-gathering capacity is not as important as high magnification within the solar system. The relatively small aperture of a refractor is therefore often an advantage for this kind of observing, as is the high magnification capability of its long focal length, as there is less glare from brightly lit planetary surfaces to wash out faint detail.

For purely visual lunar, planetary, binary and star cluster observing, an altazimuth refractor with slow motion controls may be perfectly adequate. If a family shares the telescope, however, an equatorial mount with a motor drive will keep objects centered in the field of view so all can share the same view. Close-up lunar and planetary photography requires such a mount and motor drive. Due to the limited light gathering of the smaller refractors, long exposure deep space nebula and galaxy photographs are rarely attempted with this type of telescope.

The drawbacks of a refractor? Except for very expensive apochromatic designs, all refractors suffer from chromatic aberration (or "spurious color"). This is an optical defect that produces a faint, and normally unobjectionable, pale violet halo around bright stars, the limb of the Moon, and the planets. Chromatic aberration becomes more visible as the aperture increases and the focal ratio decreases, although modern optical systems minimize the problem in two-element achromatic refractors – and virtually eliminate it in three to four lens apochromatic systems.

While they are light in weight and economical in smaller sizes, refractors become bulkier and considerably more expensive than reflectors or catadioptric scopes as apertures hit 4" (102mm) and above. A premium 4" apochromatic refractor typically costs and weighs four to eight times as much as a 4.5" reflector or 3.5" Maksutov-Cassegrain.

But these drawbacks aside, and if sheer light grasp is not essential – for hunting very faint galaxies, for example, where a larger reflector would have the light-gathering edge – the clarity, contrast, and sheer image quality of a good refractor is well worth your consideration.

REFRACTOR REPORT CARDS
(used in excellent seeing conditions and with no light pollution; adapted from Astronomy Magazine):

E = excellent; VG = very good; G = good; F = fair; P = poor.

Small aperture (2" to 3") "toy store/bargain" refractors:
Price range: $100-$200
Portability: E
Ease of setup: E
Ease of use: F
Performance on the Moon: F
Performance on comets: P
Performance on double stars: P
Performance on galaxies and nebulas: P
Performance on planets: P

Small aperture (3" to 4") achromatic refractors:
Price range: $200-$800
Portability: E
Ease of setup: G
Ease of use: G
Performance on the Moon: E
Performance on comets: F
Performance on double stars: VG
Performance on galaxies and nebulas: F
Performance on planets: VG

Medium aperture (4" to 5") apochromatic refractors:
Price range: $700-$10,000
Portability: VG
Ease of setup: E
Ease of use: VG
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: VG
Performance on galaxies and nebulas: G
Performance on planets: VG

Large aperture (5" to 8") achromatic refractors:
Price range: $800-$3200
Portability: F to VG
Ease of setup: G+
Ease of use: VG
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: E
Performance on galaxies and nebulas: G
Performance on planets: E

Large aperture (6" to 8") apochromatic refractors:
Price range: $5000-$27,000 and up
Portability: F
Ease of setup: F
Ease of use: VG
Performance on the Moon: E
Performance on comets: VG
Performance on double stars: E
Performance on galaxies and nebulas: G
Performance on planets: E

Source:http://www.astronomics.com/main/category.asp/catalog_name/Astronomics/category_name/Why%20buy%20a%20refractor?/Page/1

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Galileo's Telescope of Palomar

Palomar is an Italian company that has been one of the leading traditional Florentine optic companies since 1956. The current management has decided to develop its bent for design by skilfully combining past and present abilities.

On July 12th 2011 The Awards Ceremony for the XXII Compasso d’Oro has been held, for the first time, in Rome at MACRO al Testaccio, La Pelanda.
Galileo’s Telescope has been awarded with the Honorable Mention XXII Compasso d’Oro 2011.

This object produced by Palomar is collected and kept in the Historical Collection of the Compasso d’Oro Award which has been declared to be “of exceptional artistic and historical interest” and included it in Italy’s national heritage


Inspired by the telescope built by Galileo in 1609, this instrument copies the original form, focal lenght (1 meter) and construction material.

Modern optical technologies make this telescope perfect for quality astronomical observation. This versatile instrument permits observing the moon, the major planets and other celestial bodies scattered through the solar system, and is also a powerful earthbound spyglass.

A novel, original object that bridges past and present; a contemporary revisitation of timeless form and function
Design: Odoardo Fioravanti


Specifications:

•Optical glass, abs, metal
•Tube: wood or aluminium
•Objective lens: Ø 60 mm
•Focal length: 1000 mm
•Magnifications: 67x, 80x, 100x with three eyepieces as standard equipment

Price :Galileo's Telescopes have two versions. Economy vesion is made of Aluminium.
Aluminium :100 Euro.
Wood :252 Euro.

Source : http://www.europeanconsumerschoice.org/house/palomar/

http://www.palomarweb.com/web/tienda/products/view/3

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