Beginner’s Guide to Astronomy – Refractor Telescopes

If you ask someone to describe or draw a telescope, nine times out of ten it will be a refractor.

The refractor telescope is quite possibly the most common or easily recognized telescope. It is a very simple design, which has been around for hundreds of years.

The history of the refractor is that it was first invented in the Netherlands in 1608, and is credited to 3 individuals; Hans Lippershey, Zacharias Janssen – spectacle-makers and Jacob Metius.

In 1609 Galileo Galilei heard about the refracting telescope and made his own design, publically announcing his invention and further developing it through extensive experimentation. Galileo’s friend Johannes Kepler further experimented with the design, introducing convex lenses at both ends, improving the operation of the telescope.

Many advances were made and the refracting telescope became the primary instrument for astronomical observations, but there was one problem; they were huge and some were many tens of feet long!

But now, after more than 400 years and — luckily — through advances in know-how and technology, the refractor has become much more powerful and compact than some of the behemoths in the early days.

Refractors or refracting telescopes employ a simple optical system comprising of a hollow tube with a large primary or “objective lens” at one end, which refracts light collected by the objective lens and bends light rays to make them converge at a focal point.

Light waves which enter at an angle converge on the focal plane. It is the combination of both which form an image that is further refracted and magnified by a secondary lens which is actually the eyepiece. Different eyepieces give different magnifications.

The larger the size of the objective or primary lens = more light gathered. So a 6 inch refractor gathers more light than a 2 inch one. This means more detail can be seen.

There are two main types of refractor telescopes: “Chromatic” – entry level and upwards with 2 lens elements and “Apochromatic” – premium, advanced and expert level telescopes with 3 or more very high quality lens elements with exotic mixes of materials.

Chromatic refractor telescopes are particularly good for observing bright objects such as the moon, planets and resolving things like double stars, but many astronomers who image deep sky and other objects use very high quality apochromatic refractors, due to their superior optics.

Refractor telescopes are very low maintenance due to being a sealed system and it is a simple case of setup and enjoy, without the fiddling lengthy setup times you may get with other telescopes.

Refractors give clean and crisp views due to the sealed nature, unlike other telescopes like Newtonians which are subject to cooling and air turbulence issues.

Due to their small size they are very portable and can also be used for terrestrial observations the same as binoculars, which are basically two refractors bolted together.

Telescope Eyepieces: The Weakest Link

Do you have a new telescope, or are you considering buying a new one? Hopefully, you have chosen a telescope with the best specifications for your budget, but before you can truly get the best out of your wonderful new window on the cosmos, you need to have something even more important than the scope – Eyepieces!

A lot of people new to astronomy, or new to buying astronomy equipment tend to concentrate on telescopes and unfortunately overlook eyepieces, settling for the basic set of 2 or 3 that come with the new telescope.

Eyepieces are probably the most important part of your observing equipment, as they are at the heart of your setup and can make your observing experience fantastic or disastrous, or make an average telescope great or an excellent telescope bad.

The Basics

Eyepieces are the part you look through and are responsible for magnification of the objects you see through the telescope. They come in many different magnifications and types, but it’s not rocket science. You will soon learn what eyepieces work well for seeing different astronomical objects.

Telescope eyepieces are designed to fit into the focuser of the telescope. Depending on your telescope, they come in two sizes 1.25” or 2” and there is .965” which is an older size and pretty much obsolete, unless you have an old telescope. Most telescopes can be fitted with adapters so both eyepiece sizes can be used.

Magnification

The magnifying power of any eyepiece is a simple equation expressed in millimetres: Divide the focal length of the telescope by the focal length of the eyepiece and your answer is the amount of magnification. Long focal length eyepieces such as 32mm and 25mm are lower magnification, while lower numbers like 10mm and 5mm are magnifying powerhouses.

It is always good practice to start observing an object with a lower power eyepiece such as a 40mm and gradually build up to higher powered eyepieces such as 10mm or lower. The reason for this is the telescope, human eye, seeing conditions and object being observed are all variable. Starting off with a high power such as 4.7mm may be a struggle.

Fainter objects such as nebula and galaxies are usually seen better with lower powers and you can really ramp up the power with bright objects like the moon.

Below are rough guides and are dependent on the telescope you use:

2mm-4.9mm Eyepieces: These are very high magnification and very difficult to use unless seeing conditions are perfect and the object observed is very bright, like the moon.

5mm – 6.9mm Eyepieces: These are good on bright objects such as the moon and bright planets, but are still very high power and work best with steady seeing conditions.

7mm – 9.9mm Eyepieces: These are very comfortable high magnification eyepieces and are excellent for observing brighter objects, a must for any eyepiece collection.

10mm – 13.9mm Eyepieces: These work well for all objects including brighter nebula and galaxies a good mid/high range magnification.

14mm – 17.9mm Eyepieces: These are a great mid range magnification and will help resolve globular clusters, galaxy details and planetary nebulae.

18mm – 24.9mm Eyepieces: These will work nicely to show wide field and extended objects, great mid-range magnification for objects like galaxy clusters and large open clusters.

25mm – 30.9mm Eyepieces: These are wider field eyepieces for large nebula and open clusters. A good finder eyepiece for locating objects before moving to higher powers.

31mm – 40mm Eyepieces: These are excellent for extended views and large star fields and make excellent finder eyepieces before moving to higher powers.

Eye Relief

Eye relief is the distance from the last surface of an eyepiece at which the eye can obtain the full viewing angle. If a viewer’s eye is outside this distance, a reduced field of view will be obtained and viewing the image through the eyepiece can be difficult. Generally longer eye relief is preferred.

Eye Relief Credit: qwiki.com

Apparent Field of View

This is the apparent size of the image in the eyepiece and can range from about 35 to 100 degrees. Larger fields of view are more desired.

Apparent Field of View Credit: starizona.com

Types of Eyepiece

There are many different eyepiece types, some old and now obsolete, some simple and some advanced.

The different types of eyepiece are purely governed by the configuration of the glass and lenses inside the eyepiece. Some giving exceptional eye relief, wide fields of view, colour correction etc.

Some different brands of eyepiece include: Huygens, Ramsden, Kellner, Plössl, Orthoscopic and Kellner.

The most common and popular eyepiece type is the Plössl due to its good all round performance, good eye relief, approximate 50 degree field of view, pinpoint sharpness and good contrast. Plössl eyepieces are made by many manufacturers now, but there are excellent examples from manufacturers such as Meade and Televue.

Finally we have exotic eyepieces such as Super Wide and Ultra Wide which are usually 2” eyepieces, with higher powers up to around 4.7mm at 1.25” and are usually in the domain of the large Dobsonian or Newtonian telescope user, but are just at home on smaller telescopes such as refractors or Cassegrains.

These eyepieces sport amazing eye relief and huge “port hole” 80 – 100 degree views with fully loaded premium optics, which are very forgiving on telescopes with optical aberrations and other problems. They can make average or poor telescopes great, but there is a cost; an example of which is my 14mm Ultra Wide which cost £500 ($800) just for one eyepiece and I have a full set! Combined, my eyepieces are worth much, much more than the telescopes they are used on, but it’s worth it!

Eyepieces are the most important part of your observing equipment, choose them and use them well, which will help you enjoy observing through your telescope.

Why are Dobsonian Telescopes a Favorite Among Amateur Astronomers?

Dobsonian Telescope
The Meade 16" LightBridge

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Welcome to the scary and expensive world of buying your first, or replacing your old telescope!

I am asked all the time “What telescope should I buy” or “What telescope do I need to see X with?” Nine times out of ten, I recommend a Dobsonian Telescope.

So what is a Dobsonian telescope and why are they so good? Read on to find out why.

A Dobsonian is simplicity in itself; a simple set of optics on a simple mount. But don’t be fooled by this simplicity. Dobsonian telescopes are incredibly good and are great for amateurs and professional astronomers alike. They are also very economical compared to other telescopes.

The optical part of the telescope or OTA (Optical Tube Assembly) is the same as a Newtonian reflector telescope. It consists of a primary parabolic mirror and a flat secondary mirror in an open ended tube, with a focuser for an eyepiece set on the side. Light enters the tube, reflects off of the primary mirror at the base and is then focused onto the smaller flat secondary mirror and then finally, into an eyepiece. Simple!

Credit Skywatcher.net

The benefit of this type of optical arrangement is the telescopes light gathering ability. The more light gathered, equals more fainter objects to be seen. A light bucket!

Dobsonian/Newtonian telescopes have a big advantage over telescopes with lenses such as refractors and Cassegrain telescopes, as mirrors are a lot cheaper to make than lenses. Plus they can be a lot bigger!

Both Dobsonian and Newtonian telescopes are measured by the size of the diameter of their primary (big) mirror. Dobsonian sizes range from starter scopes of 6 inches up to 30 inches, but common sizes are 8 to 16 inches in diameter. They can be many times larger and less expensive to produce than scopes with lenses.

The second part of a Dobsonian telescope is the mount. As with the optical part the mount is just as simple, if not more so! A basic manual mount which supports the optical tube and can be manually moved by hand in the Altitude (up/down) and Azimuth (left/right) axis.

The mount is usually made from wood or metal with bearings and support for the two axis of movement. More so lately, some manufacturers have put GoTo systems with motors on some Dobsonian mounts. Personally I think it’s a bit over kill for a Dobsonian, as finding objects manually by star hopping or other manual methods helps you learn the sky better and can be fun.

Dobsonian

Resist the urge to spend lots of money on small computerized scopes that will eventually never get used, as they can be too complicated or you may not see much through them apart from the brightest objects such as the Moon. A Dobsonian is a great all-around telescope, and are available in almost all telescope stores. Some people make their own homemade Dobsonian scopes too!

Due to the nature of the Alt-Az mount, Dobsonians are not suitable for long exposure astro imaging. For that you will need an equatorial mount, which will track the stars equatorially. You may have some success with webcam imaging with some of the GoTo Mounts though.

Skywatcher 10 inch Dobsonian Credit sherwoods-photo.com

Dobsonian telescopes are designed to be simple, easy to use and gather as much light as possible. Because of this robust simplicity, they are very economical and popular with astronomers of all levels of ability. My own and most favourite telescope is my Skywatcher 10-inch Dobsonian and I will probably be using it for many more years to come, as it is difficult to beat!

The name of the Dobsonian telescope comes from its creator John Dobson, who combined the simple design of the Newtonian telescope with the Alt-Azimuth mount. He originally made simple homemade scopes from household materials and ground mirrors out of the glass of old ship portholes.

John Dobson is the grandfather of Sidewalk Astronomy and co-founder of the San Francisco Sidewalk Astronomers.

Credit cruxis.com

Choosing a New Telescope – GoTo or not GoTo

Guide to Meade Telescopes
MeadeETX125PE

I am often asked by people “I’m a beginner, so what telescope should I buy?” Or more often, what GoTo telescope would I recommend for someone starting out in astronomy?

When venturing out and buying your first telescope, there are a number of factors to consider, but because of glossy advertising and our current digital age, the first telescope that people think of is a GoTo.

Do you really need a GoTo or would a manual telescope suffice? In order to make a good decision on what telescope to buy, you need to decide on what you want to use the telescope for — observing, photography, or both and does it need to be portable or not? This will help you make the best decision for the mount of your telescope.

GoTo telescopes are usually advertised as being fully automatic and once they have set themselves up, or are set up by the user, they can access and track and many thousands of stars or objects with just a simple touch of a button. These features have made GoTo scopes are very desirable with many astrophotographers.

Manual telescopes are not automatic or driven by motors as GoTo scopes are. They are predominantly used for observing (using your eyes instead of a camera) and the scope is moved by hand or by levers by the user to find different objects in the eyepiece. Manual telescopes usually have a finder scope, red dot finder or laser finder to aid in finding objects in the eyepiece. They are unable to track objects, which can make them unsuitable for photography.

GoTo Vs Manual
Compared to GoTo telescopes, manual telescopes are much more economical as you are basically buying a very simple mount and an optical tube assembly (the telescope tube, or OTA). With GoTo you are adding electronics and control mechanisms to drive the scope, which can add heavily to the cost. A small GoTo telescope could cost the same as a lot larger manual Dobsonian telescope.

Good GoTo telescopes make astrophotography very accessible and enjoyable, especially with the addition of cameras and other kits. As opposed to manual scopes, GoTos can be used for long exposure astrophotography. Be aware though, that much astrophotography is done with very expensive imaging equipment, but good results can be achieved with web cams and DSLR cameras.

Manual telescopes are brilliant at helping you discover and learn the sky as you have to actually hunt or star hop for different objects. I once met a person who had been using a GoTo telescope heavily for a year, and at a star party I asked her to show some kids where a well known star was with my laser pointer, she didn’t know because she was used to her GoTo scope taking her to objects.

So which one should you buy?
I would recommend for pure visual observing a manual telescope such as a large Dobsonian or Newtonian telescope. The human eye needs as much light to enter it as possible to see things in the dark, so a big aperture or mirror means greater light gathering and more light entering your eye, so you can see more. What you saved by not having GoTo, you can spend on increasing the size of your telescope.

If you want to add photography or imaging capabilities then I would definitely recommend a good quality GoTo scope or mount. You will get a smaller aperture compared to the manual scope for the same money, but the scope will track for astro-imaging and can also be used for visual observing. Be prepared to spend a lot more money, though.

Consider how you want to use your telescope and the size of your budget. Avoid buying low end, cheap, budget, or what is known as “department store” telescopes to avoid disappointment. Save up a little longer and get a good telescope. Visit your local astronomy store or telescope distributor and before you buy ask an astronomer, they will be glad to help.

I hope you enjoy your new telescope for many years to come 🙂

Dobsonian Telescope

Great Binoculars For Kids – Celestron 12X25 UpClose Binoculars


Are you looking for a great pair of binoculars for kids – but want optics good enough for demanding adults? Then you really need to check out the Celestron 12X25 UpClose binoculars for astronomy . These mighty little midgets have a whole lot going for them, including a great view at a moment’s notice.

When I first picked up a pair of Celestron 12X25 binoculars, I wasn’t expecting very much. After all, we’re talking about a pair of binoculars that when folded in their case are small enough to easily fit in your jacket or jeans pocket comfortably. What could something that small really do? As always, I give every product I test the benefit of the doubt and I was about to find out. Thanks to the generosity of OPT, several pairs of these were donated to benefit our children’s binocular observing program at the Observatory and it was time to hand them out along with the other binoculars we traditionally use. As the kids inspected their binoculars, I inspected mine, too. Since my binocular experience tends toward astronomy, I wasn’t overly familiar with the roof prism design and I was curious. Could something so small really be of practical use? And, what’s more, could something that inexpensive be of lasting quality? Well, for a person that’s usually the one giving lessons, I was about to get one.

Hands on, you’re not grabbing on to cheap plastic construction. These are binoculars that will survive an accidental drop and come back for more. The Celestron 12X25 UpClose binoculars are solidly made with a rubberized overcoating that will resist denting, ambient dew and moisture and provide a sure grip for all size hands. Their swivel open action is firm, but not stiff, and holds the interpupillary distance exactly where you need it. I was also surprised to find that they had a right eye diopter, as well as a central focus wheel. Now, it was time for me to give lessons as I explained to my students how to “personalize” binoculars for their own vision:

  • Hold the binoculars near your eyes, but don’t cram them up against them. Spread the binoculars apart until the center of each lens matches comfortably with the distance between each pupil of your eyes.
  • Locate the focusing ring called the right eye diopter and close your left eye. Choose a focal point by where you will be doing most of your viewing. For example, a bright star if you’re doing astronomy or a distant tree if you’re doing nature studies. Now, slowly turn the diopter until what you see on the right side comes into focus.
  • With both eyes open, use the center focus wheel to fine tune the image and you’re ready to go!

Because roof prism binoculars aren’t particularly well suited to astronomy, the 2.1 mm exit pupil left something to be desired, but the 10 mm of eye relief was quite comfortable with enough focus travel to match every eyesight need in the group. At 9 ounces (255.15 grams) in weight, the Celestron 12X25 UpClose binoculars are very easy for an adult to hold steady with one hand and absolutely the perfect weight for a child. Despite their diminutive size, you can “feel” that you’re holding on to a real pair of binoculars… and they perform like it, too. While the 25 mm (0.98 inch) objective lens isn’t going to gather in light like the Hubble Space Telescope, it does give very satisfactory views of brighter astronomy objects such as the Orion Nebula, the Andromeda Galaxy, magnitude 6-7 star clusters and more. The 12X magnification factor is also very satisfactory, offering enough resolution to pick apart brighter stars in clusters and distinguish individual larger craters on the Moon. While the kids raced all over the night sky with them, I just kinda’ stood there and grinned… Thinking of what sweet little wide angle spotters they’d make for those of us who need just a little “help” with certain star fields at times.

In order to be fair, I also used the Celestron 12X25 UpClose binoculars for what they were designed for – terrestrial use. During the winter months, I have a thing about feeding the local birds and identifying each visiting species. With a close focus of 14 feet (4.27 meters), these exceptional little binoculars allow me just the right amount of distance to enjoy the “up close” views of the outdoor bird feeder from my indoor easy chair – yet still be able to tell a nuthatch from a chickadee in a more distant tree. The images are crisp and clean with no spurious colors or reflections even in bright natural light situations. As for artificial light situations? Well, they are definitely fun enough to turn a large tabby cat into a stalking tiger. (silly kitty… there’s glass between you and those birds.)

All in all, the Celestron 12X25 UpClose Binoculars are absolutely perfect for a child and a compact and useful tool for adults. Because they are “real” binoculars, your kids will respect them for their quality and performance. And, because they are Celestron, you can be assured of rugged durability – backed up by a Lifetime No-Fault Warranty. Put a pair into your son or daughter’s hands and let their imaginations fly. Give them to your grandkids. The only way they could harm them is to lose them!

So stay away from mine…. 😉

Many thanks to OPT for their generous donation and providing the binoculars for review. See this link for purchase information. You can also purchase them for a similiar price from other premium worldwide Celestron dealers such as Optics Planet (US), Hands-On Optics (US), Picstop (UK), Telescopes.com (US), and Canadian Telescopes (CA) .
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Why Are There So Many Celestron Reviews?

Collimation
Collimation

I’ve had a couple of readers write me, wondering what was going on with all the Celestron telescope reviews. Are we sponsored by Celestron, or something? Nope. Let me just make this clear. We don’t get any money from any of the telescope manufacturers, or any kind of sponsorship at all. If and when we do, I’ll let you know.

So far, Celestron, Vixen and Sky Watcher are the only telescope manufacturers willing to send out a telescope for us to review, and then willing to pay for the return shipping to take it back off our hands again. If I have to pay to receive a telescope, or ship it back, we can’t afford to review it on Universe Today.

I know that really sets the bar pretty low. Universe Today received almost 2 million visitors last month, with 50,000 people subscribed to the RSS feed and daily email newsletter. Many of them are very interested in owning a telescope and would love to read about all the telescopes on the market. But I’m honestly exhausted trying to justify this to the manufacturers.

But so we’re clear, we’re not paid to give Celestron good reviews. If Tammy comes across as kind of enthusiastic in her reviews, well… that’s Tammy; she’s an enthusiastic force of nature. The manufacturers pay to ship the telescopes to and from our reviewers (well, Tammy), and then I pay Tammy for her reviews. If the telescope companies advertise on Universe Today, through Google, or through direct advertising, it doesn’t influence what Tammy has to say about them.

And if you’re a telescope manufacturer who wants to join this elite club of companies getting reviews on Universe Today, you just need to pay for the shipping. And if you want to advertise on Universe Today, just drop me an email.

P.S. I picked up a Celestron First Scope for the, uh, kids, and I really like it. Thanks to Tammy for the review, and thanks to the IYA for helping get it built.

When Everything Old Comes To New Again…

There are times when even the smallest decision can change everything about you and alter the course of others for life. You might not know it when it happens – because it may seem as insignificant as what to order for dinner, what Christmas present to choose, or what radio station you listened to that morning. But sometimes the Cosmos has a grand scheme waiting for you if you’re willing to listen. In this case, it’s the story of a Celestron telescope – one that’s endured through decades of use and three generations of star gazers.

It all began in the mid-1980’s with a “Cometron” telescope, bought to view Halley’s Comet. Those were the halcyon days before the Internet. Learning the night sky was a slow and painful process because no ready open sources were available for instructions and few places (besides the local library) available for learning. I was hard on a telescope because I didn’t know any better. Nearly a decade of use later, there wasn’t much left of that old refractor but fond memories. I was ready for bigger and better things. No more attaching the optical tube to a vise for a mount, no more squinty little eyepieces. I wanted the big time. It was Christmas 1994 and I had no idea then what kind of role that a Celestron FirstScope would end up playing in my life…

And no clue just how “big” it was going to get.

rangerThe Celestron 114 Newtonian reflector and its well-manufactured equatorial mount opened my eyes. Comet Hale-Bopp, solar eclipse chasing, sunspots, variable stars, double stars, galaxies, lunar transient phenomena, star clusters, nebula… The night sky became my companion and the FirstScope my teacher. Together we learned to read complicated star charts, use setting circles, judge magnitudes and sky conditions, take notes and do astronomical sketching. Many nights and days were spent observing – be it with my old dog – or with my nearly grown sons. It was a world we traveled in alone – never knowing there were others that enjoyed the same hobby. Aperture fever soon enough had me in its grip and what better way to cure a fever than with a big Celestron Starhopper?

By the time telescope size had increased, so the world of communications had expanded. The Internet had entered my life in the form of a WebTV unit. The boys had long ago discovered girls and a new dog replaced an old one. When my Mother told me she heard about a some people meeting with telescopes on the radio, I finally knew I wasn’t alone. It was the first time the Celestron 114 was about to travel away from my rural backyard – and the beginning of its many journeys around the world. The event was my first public outreach and my introduction to Warren Rupp Observatory. From there, I knew there wasn’t any more going ”back home”.

on_the_hillEven though I had met some members of the astronomy club at their outreach event, I was shy my first night at the Observatory – afraid to put that little telescope alongside such fine, big company. Who was I but an older woman with no professional experience next to these guys? An hour after dark later, I knew who I was. I was woman with a star chart in her head and a little telescope that could mop up the skies. One that would eventually change the history of the Observatory just as surely as volunteering at the Observatory changed me…

And everything old became new again.

Did we travel? Oh, yes. The Celestron FirstScope has been all over the continental United States. We’ve quested in the south for Omega Centauri and chased eclipses from border to border. It’s been unceremoniously stuffed in the trunk of many sports cars to be hauled across state lines on vacations and off to public outreach events. It’s been shipped across the world and battered in the belly of an airplane. For months at a time, the FirstScope would often stay fully assembled so it could be quickly set outside the garage for daily solar, lunar and planetary viewing. It watched my sons grow as we exchanged confidences and solved problems under the comfortable cloak of darkness. It saw the birth of my grandchildren and their first views of the stars. It was my workhorse, my friend, my mentor… my telescope.

As time went on, I grew to trust Celestron’s durable quality. Like creating new recipes in the kitchen, Celestron came out with many designs that ended up part of my personal telescope fleet. While there were tasty treats that might have only appealed to a few and lasted for awhile, there were many winner dinners which have also endured the test of time to become family favorites. Yet, no matter how many times I might upgrade, trade or replace a Celestron telescope, I never had the heart to let go of the enduring FirstScope. Somehow, it felt like there was a reason I had to keep it around.

celeThe years passed and my hobby in astronomy soon turned into a career. Although I am not a professional astronomer, I realized a need many years ago to open friendly, natural communications about astronomy and how to use a telescope. Although I learned the “hard” way, I knew I couldn’t keep what I had learned to myself. Sharing the sky and the passion for what I do became my primary goal. The Celestron 114 followed me to what I thought was to be a permanent home at Warren Rupp Observatory as an historic piece – but it had other plans. Every time I looked at it, it would all but walk around on its three black legs and cry to be used again at more than just public nights.

And it didn’t have long to wait…

solar_mikeOnce in awhile you meet up with karma and you’ll know it when it comes to call. Our Observatory outreach had encouraged a new member, and he and his grandson have a passion which matches perfectly with everything the Celestron 114 FirstScope stands for. Many months ago, I told him to take the scope home with him and learn… it deserved to be used again. Although he was a little bit afraid of it, he took my advice and he and his grandson embarked upon a celestial journey that’s only beginning for them. Into their hands has come a case of Celestron eyepieces and filters. And, like long ago, that same old solar filter and a new canine companion to complete the circle.

DSC03687So what has become of Celestron FirstScope service and Warren Rupp Observatory? Just as surely as the Earth orbits the Sun, what goes around comes around. OPT Telescopes heard about our outreach efforts and understood that in order for us to keep our educational programs free to the public that we’d need donations… and donate they did. Not only do the many Celestron telescopes of our members serve the public, but OPT provided us with a fleet of Celestron FirstScope Telescopes and Celestron FirstScope Accessory Kits to serve the thousands of children we educate about the night sky each year. Because sometimes…

Everything old comes to new again.

For Christmas – Don’t Think Nintendo Wii… Think Celestron Omni


Are you looking for the perfect family Christmas gift? Well, stop right there on drawing out your credit card, because there is no such thing. Every family is different. Different needs, different circumstances… even different financial situations. But, what I’m here to tell you about is something I’ve found that changed the way my science and nature-minded family looked at things. It’s Omni… And time waits for no man.

A little over a month ago Ms. M.M. from Celestron offered to send me a telescope of my choice for a Universe Today product review. Now, putting an offer like that to an avid astronomer is kinda’ like taking a fat lady to a smörgåsbord – I wasn’t quite sure of where to start. Oh, sure. I could be polite and start in the salad section and ask for a Celestron AstroMaster 114 EQ Reflector Telescope. After having looked at them, they’d make the perfect starter telescope for all ages: a very decent telescope that would withstand the time test. Or, I could go straight to the prime rib and request a Celestron CGE Pro 1100 EdgeHD Telescope… rare, please. These are very serious telescopes meant for very serious astronomers. There’s no joking around with this fine piece of equipment. But what I’m after isn’t at either end of the scale. What I want is something that touches your heart and your head… Not just your taste buds.

And I want to review it for Christmas…

Every year at this time I marvel at all the new technology that comes out. We’ve got net books and Kindle books… cell phone with apps for everything from milking your goat to making natural gas noises with a blade of grass. There’s dolls that grow hair while spouting MP3 songs and remote controlled helicopters that carry their own weapons of mass destruction. We’ve got video games that tell us we’re old and fat and offer to tone us up. And, we’ve even got last year’s “can’t find it anywhere at any price” Wii system that’s now affordable 365 days after I paid twice as much as I should have for it. Oh, don’t get me wrong. It’s a fun toy. There have been many wonderful all-age family bowling matches and slug fests that involved a lot of laughter, but once the game was over? It was over. It was fun at the time, but it didn’t spark anything inside the brain.

“Allys” changed things.

What I asked for from Celestron was the Omni XLT 150 Newtonian Reflector Telescope. Why? Because no one ever talks about them, and even fewer people know about them. The reason the Celestron Omni isn’t a more celebrated telescope is because it is pure telescope. It doesn’t have bells and whistles. It doesn’t have a GoTo system that will whisk you away on a magic carpet until the batteries run out. It doesn’t have a mass of marketing claims behind it – or designs “re-worked” to be affordable. It only comes in two styles – refractor or reflector. And it stands for a principle.

Omni is the belief that all religions contain a core recognition of the same Deity… and so it is with astronomy. For those of us who practice astronomy religiously, we feel a certain kindred-ship with all who love the science and beauty of the night sky, be it the lady with the Moon and stars earrings, or the skinny dude with the “Astronomers Like To Do It With Mirrors” t-shirt. And, the Celestron Omni 150 XLT reflector telescope stands exactly for that. It is a core telescope – able to recognize many the same Cosmic delights as the Hubble Telescope, just as it reveals what you can find in an old pair of binoculars. After all, we’re all in this game together, aren’t we?

9225-LI don’t know what magic this telescope came packaged with, but the day it entered my home, it captured us all. My 20-year old son was the one to carry in the box and watched me open it. I was amazed at his response when he caught the first glimpse of the midnight blue paint and snow white trim: “Mom? Can I put that together for you?” Of course, my first thought was no way. After all, this is a loaner scope and one wrong move could mean monetary disaster. However, I kept an open mind. First off, the young man was raised around telescopes and second, just how intuitive and easy will it really go together? I needn’t have worried. Johnny Mnemonic had it fully assembled and balanced in just a few minutes and then we both stood back and admired perhaps one of the finest looking telescopes I’ve seen in a long, long time.

omni_rear_cellFrom top to bottom, the Celestron Omni XLT 150 stakes its claim on durability loud and clear. Every part, and I do mean every part is high quality. The optical tube is absolutely the right thickness and the mirror cell and secondary are totally solid construction. The whole midnight blue optical tube assembly is custom trimmed in white. Even the tube rings are excellent, no flapping around like broken bird wings when released. The rack and pinion 1.25″ focuser is not a “cut corners” afterthought – it’s top quality with precise movements and no slop… no plastic knobs and cheap gears. The 6X30 optical finder scope is just the right size and mounted with a heavy-duty bracket that’s going to take a whack or two in the dark without losing its alignment. But that’s far from all…

omni_mirrorsFor those of us who appreciate our optics, then take a look inside the tube. Pristine mirrors? You bet. What you’re looking at is hand selected, high quality optics made from the finest glass available. Only one thing could make it better and that’s Celestron’s StarBright coatings for maximized light transmission. We’re talking about optics on a 6″ Newtonian reflector telescope with a limiting stellar magnitude of 13.4 and 0.76 arc seconds of resolving power! So what’s holding it up? Try a Celestron CG-4 German Equatorial Mount. The CG-4 is a new experience for me, and I’ll tell you right now that I’m impressed… and not just with its stainless steel 1.75″ legs capped with little white bobby socks, either. We’re talking about a rugged equatorial mount with ball bearings in both axis able to carry at least a 20 pound payload. A single knob mounts the head, just as a single shaft continues into the spreader of the tripod. The supplied weights are exactly right and the bubble level and polar axis finder make it all the sweeter. The slow motion controls are snugged into the mount body, not spangling around on too long arms. If I thought the Vixen-mount was great, then there’s a good reason I like this one… it evolved from the Vixen GP2. There’s even an extra “safety” bolt on the quick release to stop an accident before it starts. Now all we need are some clear nights to check out the performance!

Allys stood in my living room for many nights before I finally got clear sky. I’m not even sure of why I started calling the Celestron Omni XLT 150 by a name, because I’ve never named a telescope before. But the more I look at it, the more it reminds me of an Allis-Chalmers tractor… something you’ll see out in the field for the next 50 or more years. And, when we did get out in the field, I knew 50 years wasn’t going to be enough. I had also asked for an assortment of Celestron Omni eyepieces to accompany it, and when I homed in on M67 and saw absolutely no spherical aberration at both low and high magnification factors, I knew I had my hands on an optical standard. Exceptional configurations don’t need gimmicks to set them apart in the field. At a little over a 50 degree apparent field of view, the Celestron Omni Plossls worked absolutely perfectly with the f/5 focal ratio. There’s no “ghosting” and great color correction. Who needs twice as much field with an eyepiece that you’d be afraid your grandkids might touch when you’ve got one that’s delivering razor sharp lunar images at high magnification and diamond dust star fields at low?

Over the weeks and through lunacy I put the Omni 150 through every course I know. At 6″ aperture, it lights up Messier objects with tiny details. It is quite capable of magnitude 12 galaxies. Its 750mm focal length and focal ratio of f/5 presents nebulae the way you want to see them. Little things started to mean a lot… Like how fast any vibration in the mount stopped when you’d tweak the slow motion controls while watching Jupiter at high power or just how smooth and well-balanced the whole system is. I enjoyed superior colors from the singular stars in M50 to the gas-blue flame of Hubble’s Variable Nebula (NGC 2661). This is not a little telescope nor is it a cheap one. It’s a telescope that needs your input to make it work and it delivers back with pristine views and rock solid stability. It is a telescope capable of being turned towards astrophotography – or simply enjoyed year after year.

allysWhen I was finished in the evenings, I’d return the Celestron Omni XLT 150 back to the corner of my living room. After all, I can’t be banging around scope that isn’t mine! But what the Omni did for those who entered my home is what is incredible. Not one person, from my parents to my grandchildren were able to resist that telescope. Everyone comments on its good looks and heavy-duty appearance. We virtually lived for a moment of clear sky when we could race outside to look at the Moon or try to spot a polar cap on Mars. Can you say that about a Wii? My grandchildren might have bowled a game or two, but they spent their entire vacation peeking out my windows at night wanting to hunt comets and see where stars are born. Can a video game compete with that? If one can use an Omni to travel in time, then watch a 20-year old explain to his girlfriend what’s going on inside the Pleiades instead of what’s on his latest graphics card. You might get a senior citizen to play a game or two, but when was the last time the ones you know were willing to stand outdoors in the cold to look at Moon, huh? You see, the Celestron Omni XLT 150 might cost twice as much as a Nintendo Wii… but what it did was worth far more.

As of now, I still haven’t returned the Celestron Omni XLT 150 to Celestron. What I’ve done is something I’ve never done before – offer to sell some of my other telescopes so I can buy it. That midnight blue and snow white magic walked into my life and now I don’t want to let it go. When I look through it, I half expect to see two indicator lights somewhere – one red, one green. When I stare into a distant galaxy or count stars in a galactic cluster light years away, they shall indicate whether the flow of history has been tampered with. The steady green light means that history was as it should be, and the red flash light means the only history that’s going to be altered is my own as I check out my book of charts in the dark.

Time waits for no man…

My many thanks to Celestron for giving me the great experience of working with the Omni 150XLT and I want to keep it. If you’d like a Celestron Omni 150XLT Newtonian Reflector for yourself or your family, you can find one at Celestron’s premier dealers such as OPT, telescopes.com, Scope City, High Point, Hands On Optics, Astronomics and Adorama.

The Sky-Watcher AZ4 102 Refractor Telescope… How Sweet It is!

If you’re looking for a quality refractor telescope that costs well under $400 and performs like it should cost twice as much – then you’re really going to want to take a look at the Sky-Watcher AZ4 102 Refractor Telescope. I had read some posts on the Bad Astronomy Universe Today forum about how Sky-Watcher was a new comer into the industry and people were expressing their concerns about the quality of the telescopes they manufacture. I can understand not wanting to take a chance with a fairly unknown company – so I did the logical thing. I asked for one…

According to their site: “At Sky-Watcher USA our only mission is serving the needs of serious amateur astronomers. Sky-Watcher USA is a wholly owned subsidiary of Synta Optical Technology, the world’s largest manufacturer and distributor of astronomical telescopes. Sky-Watcher is a prestigious global brand renowned for technical innovation, award-winning industrial design, and a reputation for high quality workmanship. Sky-Watcher constantly strives to introduce new and improved instrumentation to enhance the amateur astronomer’s capabilities to push the boundaries of personal exploration.”

Those are some mighty fine words, but what I really wanted to know is how well the product would live up to them. So let’s start with first things first, eh? Sky-Watcher doesn’t just hang in the USA. If you’re looking for a Sky-Watcher telescope, you aren’t limited because they have subsidiaries in both Canada and Europe. This is good news for those of you who often desire a particular type of telescope and have difficulties with shipping. The next bit of good news you’ll also like to hear is the branch company prices are all competitive with the monetary scale in the area. In other words, what a Sky-Watcher telescope costs on one exchange rate is going to be pretty daggone close on the other.

Hmmm… A company that’s not out to get you because of where you live? I like that…

Next up? Investigate Synta Optical. Rumor has it they’ve team with Celestron as well as Sky-Watcher. Well, it’s not a rumor – it’s true – and Suzhou Synta Optical Technology Co., Ltd. of China is proud to be part of it. The company offers advanced equipment, such as multi-coating machines, interference meters (Zygo brand), collimators and other instruments which are used for manufacturing optical products. And when it comes to optics, you can love it or leave it, but Celestron consistently has some of the finest optics and durable mechanics that I know, so we’re looking at a good global reputation here. If Synta is also supplying SkyWatcher, then why should the quality be any less for their name?

Hmmm… A company that’s going to produce durable quality? I like that…

Next up? New and improved. And that’s where we get down to the bottom line, isn’t it? What can be new and improved upon the time honored telescope designs we’ve all known and trusted for many, many years? Then let’s try high quality and affordability – that would be a welcome “new and improved” for us all.

SW102cSo, now it’s time to open the box the Sky-Watcher AZ4 102 Refractor Telescope came in and check it out. I was immediately impressed with the quality of the optical tube. From its glistening black with gold fleck paint, to its spotless white trim, this is one very well put together refractor. No edge is left unturned or cheaply done. At around 14 pounds, the AZ4 102 isn’t a lightweight and Sky-Watcher’s advertisements don’t even express how well made it really is. We’re talking smooth quality rack and pinion focusing with aluminum knobs – no slop in the focus – just fluid workings with enough tension that you’re not going to overshoot your mark easily. One glance at the sparkling objective and you’re going to see 2-element, color corrected achromatic lenses that are fabricated to the highest optical standards from Grade-A Crown and Flint optical glass. Each lens set is individually pitch-polished, and hand figured by a master optician ensuring premium optical performance. Each lens system is air-spaced with high transmission optical coatings – not glued together like more inferior models.

SW102dFurther into the box I find the Sky-Watcher AZ4 mount – known as the “Rock”. Again, I’m impressed with the quality for the price. Both the mount and tripod head are constructed of rigid, cast aluminum and the tublar tripod legs are 1.75″ diameter heavy duty aluminum as well. Assembly was quick and easy and I was delighted with how well centered the weight of the scope and mount fits over the tripod. Unlike some other major brands of inexpensive refractors on alt-azimuth mounts, we’re looking at good quality here… thrust-bearing surfaces well lubricated and teflon bearings… the control knobs work easily and mechanically perfect to allow you to set just the right amount of tension to make everything work with ease.

SW102bNext come the accessories. We’ve got 25mm and 10mm four-element Plossl eyepieces, a 45 degree diagonal and a red dot finder. (Yes, there’s even planetarium software, too!) While these accessories aren’t going to set any records as super high quality, they also have absolutely nothing to be ashamed of. The eyepieces and diagonal are above average, and while I’m not real keen on red dot finders, I’m also perfectly capable of using them. Once everything is together, all we need to do is wait on dark…

Refractors have a reputation for excellence on planetary objects and right now Jupiter is prime. Not only are we giving this scope first light – but we’re doing so on a cool, very steady 9/10 atmospheric platform with sweet and easy 6.0 limiting magnitude with a score of better than 8/10 on clarity. With the 25mm in a 1000mm focal length scope, we’re talking roughly 40X power and Jupiter is small and crystal clear. Immediately you could discern dimension in the Galiean moon’s positions and absolutely no color fringing was present. Drop in the 10mm and now we’re talking 100X and details begin snapping out like crazy. The larger moons can be perceived as orbs and striations and swirls in the different zonal belts become very noticeable. Again, there’s no spurious color… No aberration. No ghosts. Just tiny pinpoint stars where Jupiter’s “light pollution” doesn’t influence the picture and a razor sharp planet.

Hmmm… A 4″ chunk of glass that’s going to produce cutting edge images? I like that…

Needless to say, I watched Jupiter for a very long time. Again, I’m impressed (and so were the other discerning astronomers who were also observing at the time) with the mount quality and it lives up to its reputation of being a “Rock”. Usually I do not favor high magnification factors on an un-driven scope, either. But once you’ve set the tension and angle to your liking, you can basically guide the Sky-Watcher AZ4 102 Refractor Telescope with the touch of a finger. Just a gentle pressure to keep the scope tracking and virtually no backwash from the mount moving around.

Of course, I had to do deep sky, too. How did it perform? Reality check. It performs like a 4″ aperture telescope. the AZ4 102 isn’t going to gather more light than what its capable of – nor will it resolve better than its theoretical limitations. But… I want to push those limitations. After all, its supposed to “enhance the amateur astronomer’s capabilities to push the boundaries of personal exploration”. So… Show me.

Using an undisclosed manufacturer’s 2mm – 4mm Click-Stop Zoom eyepiece, I took this telescope to the edge and beyond. We’re talking between 500X and 250X on one of the toughest multiple stars out there – Gamma Andromeda. Before you start thinking I don’t know my business, then think again. Almach’s two primary stars, Gamma 1 and Gamma 2, are easy at even low power. Again, I am impressed with the Sky Watcher 102’s performance on color, because a warm, golden yellow and azure blue makes for a beautiful pair – but what I want to see is what I know can be done. Gamma 2 is also a binary with a .5 arc second separation. What did I find out? At around a magnitude dimmer than its companion and so very close, you have to wait on a moment of perfect stability – but brother? It’s there. You’re not going to drive a truck through the separation, but neither can you deny it once you’ve seen it.

Hmmm… A 102mm f/9.8 achromatic lens resolving out tight fits and showing great airies? I like that…

Once I’d driven it to the limits, it was simply time to relax and let the Sky-Watcher AZ4 102 Refractor just have a good time with the night. Colorful objects like the “Blue Snowball” planetary, pinpoint stars in targets like Messier 15, drooling on the Andromeda Galaxy and companions, and returning over and over again to Jupiter to watch the moons shuttle around. Yep. We stayed up all night, ending with the Orion nebula. For those of you who might wonder about the quality of a Sky-Watcher telescope? Stop wondering, because this model wasn’t the only one star tested tonight either. I guarantee you that you will not be disappointed in the quality of the telescope, nor its performance.

Hmmm… A Sky-Watcher AZ4 102 Refractor Telescope? How sweet it is!

I would sincerely like to express my appreciation to Elena Gonzalez and Joe Gordon of Sky-Watcher USA for allowing me the opportunity with this fine refractor and to the company itself for producing several other extremely fine pieces of equipment that were also tested on this night. (Future reviews will be coming!) If you are interested in purchasing a Sky-Watcher telescope, be sure to visit with their premier dealers: Skies Unlimited, Scope City, OPT Telescope, Adorama, Astronomics, Optics Planet, Great Red Spot, Telescopes.com and Orion.

Sky Scouting Out Astronomy Fun!


What happens when you mix a large group of kids with a telescope that talks? Chances are, you’ve got a recipe for loads of astronomy fun. Thanks to a generous donation of a Celestron SkyScout 90 telescope and more, the Outreach Team at Warren Rupp Observatory soon found out what it was like to take on more than 300 guests during a recent public night and just how valuable certain pieces of astronomy education equipment can be. Come on inside where it’s dark and let me show you what we’ve found…

skyscout_scopeSince the introduction of the Celestron SkyScout Personal Planetarium, amateur astronomers the world over have been delighting in its simple, easy to use format and ability to instantly identify and/or locate any celestial object visible to the unaided eye, providing educational and entertaining information, both in text and audio. Many times when you encounter a large group of people, you’ll find there are some that are just a bit too shy to ask questions, but desperately would like to explore… And handing them a Celestron SkyScout opened up a whole new world to them. But what exactly would happen if you gave them the equally easy ability to see the objects they had found with a telescope? That’s where the Celestron SkyScout Scope 90 came into play and opened up the wonders of the Comos…

NSN_logoLike all non-profit educational organizations, the Observatory simply couldn’t afford new equipment. We never charge for attending public nights – nor do we charge for giving educational programs. As a result? Well, we might always be broke… But that hasn’t stopped us from continuously being #5 in the NASA Night Sky Network Outreach standings and serving thousands of children and adults the very best in educational programming and sharing the night sky. And even as quiet as we try to be in the dark, sometimes our voice gets heard! Just like Celestron heard about UT reader Brian Sheen’s Outreach Expedition in “Canoe Africa” and donated equipment, so our need was also heard and OPT Telescope stepped forward with an equally astounding donation…

skyscout_outreach1With just a few gentle lessons from one of our Outreach Team Members, Bob Kocar, it wasn’t long until the kids soon took over our new Celestron SkyScout Scope 90. The easy to use alt-azimuth mount and tripod allows users of any age to move easily around the sky, but that wasn’t the only treat they had in store! Along with our donation package from OPT came the incredible blessing of the Celestron SkyScout Speakers. This amazing little device only took a few minutes to charge via a USB port and delivered big, big sound to anyone within the waiting circle around the scope! Now, while one child aimed the scope, another could produce the “program” to go along with it! Story after story played, but sky scouting out the astronomy fun didn’t stop there…

skyscout_outreach2With an easy to use telescope, a personal planetarium that worked like their familiar iPods, and a sky full of stars… What more could a huge group of kids and adults ask for? That’s right. More. And OPT had delivered more in the form of the Celestron Sky Scout Expansion Card – International Year of Astronomy. The next thing you know, we were hearing about all the celestial events that would be taking place this month, information on the International Year of Astronomy and highlights of important milestones in astronomy and space history. After a few bright Messier objects, a young man held up two more he had found in our box of astronomy toys and the crowd around the telescope soon grew larger as they explored the Celestron Sky Scout Expansion Card – Astronomy For Beginners and Celestron Sky Scout Expansion Card – All About The Stars.

skyscout_outreach3Does adding a dimension like the Celestron SkyScout Scope 90, the Celestron SkyScout, speakers and expansion cards really have an impact on both personal and public astronomy? You can see the results for yourself, but what you can’t see is the most important of all. For those of us who practice astronomy, we often tease that we never know a face – but we know the voice in the dark. That night the voices in the dark were busy talking about star colors and names, pointing out constellations to each other and talking about distances and facts like young Carl Sagans. For some folks, this type of equipment might not seem right – a recorded voice taking place of a live astronomer – a telescope that utilizes GPS technology and point and shoot simplicity… But for a huge group of kids who embrace new technology?

It was a night of Sky Scouting out astronomy fun!

Our many thanks go once again to Mr. Craig Weatherwax of Oceanside Photo and Telescope for your generous donation to Warren Rupp Observatory and your continued support of our UT readers. It means so very much to all of us…