"Choosing Your First Telescope" with J. Kelly Beatty

you know I get asked a lot what kind of telescope my answer is I'm looking to buy a car what kind of car should I buy and the point is that telescopes are a very individual kind of purchase so you need to think about what you want to do with it do you want to take photographs you want to throw it in the trunk of your car and go camping with it do you want to make you know discover comets with all of those things work into it I think a lot of us have an impression of what the telescope should look like and it's probably something like this a long skinny tube with a lens at one end an eyepiece at the other much as Galileo used a few hundred years ago on a nice wooden tripod or maybe a metal tripod these still exist but a lot of telescopes are very different now you can still buy nice telescopes like this usually the tubes are a little bit shorter these are called refractors because they use a Landa's at one end to collect and concentrate the light and then the eyepiece at the other end is what actually does the magnifications so I'm going to take you through the four things you should look for for a telescope first is the optics we talked about this being a refractor I'm going to move this out of the way because while it's a lovely little telescope it's probably not the one that I would recommend for you as a first-timer another kind of telescope is this called a reflector and it's called a reflector because it's got a mirror at the back end that collects and concentrates the light and again there's an eyepiece here to do that this is in fact the telescope we're going to be giving away tonight so keep an eye on this one and if I start to walk out with it stop me so this is a telescope that is a great beginner telescope it's very lightweight you can see it's very short it moves much like a tripod side to side and up and down so we have a refractor telescope a reflector the third type of telescope I didn't bring tonight is what you might call a combination of those two it uses both mirrors and lenses to collect the light they tend to be a little bit more expensive to start with so I didn't bring one of those for you two tonight now the thing about these reflectors people say well I need the most magnification possible it's really about the diameter of the tube the bigger the diameter the more lights are going to be able to collect and just for comparison I brought a big brother of this one you notice the tubes are the same diameter right a telescopes magnifying power depends in part on the focal length how long it takes the light to come to a focus so even though these have exactly the same diameter mirrors in them this telescope with the same eyepiece will magnify twice as much as this one right so again this is a matter of personal taste do you want to just like maybe just view the moon and some star clusters then the small one might be good for you if you wanted to do something that's a little bit more ambitious you want to go after some planets and spot their moons then this might be the one for you I have one other little trick I want to show you and this is where I was talking about make sure it's the right one for you this is produced by a group called astronomers Without Borders and you notice it's a little bit bigger around but this is a telescope with a secret ok this is a telescope in two minutes I can break this apart with one screwdriver and fit it in a carry-on case alright this is a beautiful little telescope all of these that I've shown you are about $200 a piece telescopes do not have to be expensive in order to be good so that's about the optics now I want to talk a little bit about the mounts as I mentioned this is a mount that swivel side to side up and down you notice there are no motors on this nice thing about these telescopes especially for kids is that they're practically bulletproof you almost can't break them well almost right and I see a knot here okay a second kind of mount that you'll see often is what's called an equatorial mount and in this case it's an it's important you notice it's kind of cockeyed here one of these axes needs to point to Polaris the North Star and there's a reason for that it makes it a little bit simpler for the telescope to track although it doesn't look like it here honestly I do not recommend an equatorial mount for a very first telescope unless you're really planning to get into it seriously they're just a little bit too complicated as if you have young kids then the third type of mount which has made a really big headway just recently is what's called computerized mounts or the very first ones were called go-to telescopes because literally there was a button on the keypad that said go to right now you haven't noticed but right now it's been quietly tracking the sky such as it can see here it comes with a GPS module so it knows where it is on the earth you need about five minutes to set these up all of the major manufacturers of telescopes produce ones like this this happens to be from a company in here in the area called IAP Tron which is based in Woburn and so with just a few clicks here on the keypad I'm going to have it go find the planet Venus and it told me that it hasn't risen yet so I have to go back and find another planet let's find the planet Jupiter there we go and so this is a really nice way you know when these were first introduced a lot of people who pood them because they in the way made stargazing too easy but for most people who live in a city I actually like this because you know a lot of us suffer from so much light pollution that we couldn't find the that whatever we're looking for just by looking through a finderscope of the sky so a telescope like this has an advantage for a beginner now I will tell you it takes a little bit of knowledge to understand it but I don't think it's anything you can't handle so that's the mounts and that's the the optics the third thing I want to talk about are the eyepieces themselves okay now imagine if you bought a car brand new car and it came with a beautiful set of Oh Misha land tires on it and you eventually use that car and then sold the car but you kept the tires and put the tires on your next car because you loved them so much that's what eyepieces are like they're very interchangeable between telescopes usually when you buy a new telescope you'll get one or two simple eyepieces that will will start you off in these eyepieces have little numbers on the side and it's counterintuitive but the lower the number the more it now magnifies okay the lower the number the more it magnifies if you see a telescope that's advertising itself as being able to say magnify 500 times and it's not talking about the quality of its optics run for the exits because most telescopes cannot handle much more than 2 or 300 power magnification it gets all blurry and mushy and it's very unsatisfying that way so those are the eyepieces now when you when you go you will not find a lot of these telescopes in the store a lot of these you'll have to think about ordering online the fourth and final thing I want to tell you about is um the the the fact that these telescopes are built for you in other words you need again as I mentioned at the beginning you need something that is going to be suitable for you it doesn't do you any good right to buy a really expensive telescopes and believe me telescopes are far can be far more expensive than this but you need to have it suitable for you and the other thing I want to mention is that you get what you pay for in a telescope if some of you have purchased a telescope already and you say bought it at a department store and say paid $70 for it you might think about returning that one then getting one of these telescopes before they get opened on on the holiday morning's because you know what it doesn't do you any good to buy a telescope that's going to frustrate you because it's so hard to use all of these telescopes here are pretty reasonably priced none of them these basic ones here that don't have the motors in them don't cost more than about two hundred and fifty dollars even this one costs about $400 with the computer built in the nice thing is that it's got this little saddle here a lot of these telescopes are interchangeable you can move them from from mountain mount so it's all good the last thing I want to leave you with is a lot of people end up buying telescopes and actually don't know anything about them right most of you when you go out to buy a car or buy furniture or something like that you have an idea of what it is that you want telescopes is like uncharted territory for a lot of people so here's a couple of guidelines I want to mention just in case you're buying one this time of year if you're buying one for your family right and for the whole family and you all want to use it then that's great and you know a good telescope can last you a lifetime really if you if you make a nice choice I have my very first telescope that I got way too many years ago and along the way I've picked up a number of these small telescopes like this and I use them all the time it's it's important to find a telescope that is going to be right for you to use for your family if you have children that are say five and six or older and you're working with them at the telescope that's a good age to get started with telescopes because when they look in the eyepiece they can have an appreciation of what you're actually looking at at the observatory where I where I teach in addition to working at skying telescope we sometimes get people who bring like their their toddlers up to the eyepiece and there's just no comprehension there if on the other hand you're buying a telescope for a child and you're basically going to stand back and let the child take care of that then then I want you to think about like seven eight as being the sort of minimum age the child needs to be able to handle it right and and be able to carry it around the nice thing about the telescopes that I'm showing you here is as I said they're really bulletproof they're pretty hard to break and so that is the key to success now the thing is once you buy that first telescope you can always think about you know moving up just like the analogy I would use is say you buy a pair of headphones right and you want to you know listen to music on your iPad or your smartphone or whatever you know you can start off with a pretty inexpensive pair of headphones and then your tastes improve you want to hear those deep bass notes and you want to hear those real high treble notes and you want everything to be clear then you move to a more expensive pair of headphones that's the same way with telescopes there is always room to grow I'm afraid to tell you this and I hope my wife isn't watching I've got 12 telescopes at home Oh 13 I just bought one this week and and that's a little bit overkill but I do find uses for each one of those and so I think you'll find that the telescope can be really a good investment for you and your family it's great to just toss into the car make sure you try to find a place that's really dark outside because a dark and far away from city lights far away from light pollution because that will improve your enjoyment quite a bit and so in closing you know these telescopes are all great and there are more expensive ones you can buy I highly recommend that you do a little window shopping kind of stay away from telescopes that are branded as being but you're your favorite department store your favorite magazine or something like that I'd be very careful to make sure that it's actually a quality telescope you'll know it's quality again you get what you pay for and with that I think I'm going to thank you very much for your attention and turn it back over today you

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Length: 12min 41sec (761 seconds)

Published: Fri Dec 27 2013