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Repost: So you got a new telescope for the holidays – A new telescope owner’s primer

This is a repost of our usual post-holiday telescope primer for new telescope owners:

So you got a new telescope for the holidays: A Quick Primer for new telescope users.

Be it X-mas, Hannukah, Kwanza, Solstice or Giftmas this is the season for getting telescopes as gifts. Sadly, many of these scopes might be rushed into usage and some critical steps might be 016skipped. This can result in a frustrating experience for a budding young astronomer who may give up their new hobby prematurely. This can be avoided if you only take the time and a few precautions to make certain you get the baby steps out of the way without too much tripping and falling.

1) Do as much as you can during daytime first!

I can’t stress this too much. Many folks assume they can assemble their telescope right out of the box at their chosen viewing spot – in the dark. Suffice it to say this is not a good idea. Assembling out of the box at the viewing site might be an extreme example but you should certainly try working your scope and getting the ‘feel’ for it during the daytime as much as possible. Take your telescope outside during the daytime and point it at a nearby tree or other object (the object should be at least 1/4 mile away). Use this object to align the finder scope (see below) as well as test how the eyepiece focuses. Try changing your eyepieces between the low and high powered ones to see how that works as well. Move the telescope in large movements as well as using the slow motion controls as well. When you do these things in the daylight you can get a much better feel for how they should work than if you try them at night. Also if you drop an eyepiece or loosen a screw you have a decent chance to find it. Get your mistakes out of the way when the sun is up.

2) Assemble your telescope properly

This should go without saying, but it is amazing how many folks skip a few steps or don’t attach parts, or don’t read the instructions properly. We’ve seen telescopes in for “repairs” just after the holidays that were just put together wrong, or some critical final steps were ignored (slow motion controls not attached, counterweights not placed). Most of the time, there are very few non-critical elements of a telescope’s construction. So be sure to follow the assembly procedure carefully. Allow yourself a couple of hours as well (maybe three hours for certain models of dobsonian telescopes) for the assembly. Don’t assume you can just put it together a 1/2 hour before you plan to head out and view.

3) Align your finder scope. Align your finder scope! ALIGN YOUR FINDER SCOPE!

Get the point? Many folks ignore this step until the last minute and we can tell you that trying to work a telescope without an aligned finger is very,very, very hard. Even the lower 084magnifications on a short focal length telescope only see a little under 1 arc degree of the sky. This is a tiny portion of the sky so hoping to find an object with just the eyepiece is really hard to do. There is a reason why almost all telescopes come with a finder scope. So make sure to align it (During the daytime per suggestion #1) . If your telescope comes with a red-dot finder instead of an optical finder scope, be certain to carefully align that as well during the daytime – and don’t forget to switch it off! A dead battery in a red dot finder is nobody’s friend.

4) Did you get an Equatorial mount? Figure out how it moves!

An equatorial mount has some great advantages over a regular altazimuth (altitude-azimuth) mount. It can track, be motorized, and the larger ones can even be used with setting circles to locate objects in the night sky. But these are only true if you take advantage of the equatorial mount’s features and set it up properly. During the daytime (suggestion #1 again!) try a rudimentary set-up of the equatorial mount. This does not have to be super accurate as some telescope’s instruction manuals may require, just enough to get mostly accurate tracking for a little while. Perhaps more importantly, get a feel for how the telescope moves – you are used to moving things in an up/down left/right fashion. Now you need to get used to moving the telescope in declination and right ascension. Try moving the telescope from one target to another using the mount properly during the daytime to get a better sense of it. One thing to keep in mind is that the counterweight is there for a reason – it shouldn’t be pointing down all the time.

If you have a larger Equatorial mount keep in mind that you can use the setting circles to help find objects in the night sky with the help of a star atlas. But this means you have to learn to use it. Read your instruction manual carefully. You might also consider downloading a Sidereal Time app for you smartphone. You’ll see why once you figure out the details of using your Equatorial mount.

5) Choose your first targets wisely!

Many folks go out with their telescope and just point it at the brightest thing in the sky. This is fine if the brightest object is a planet or the Moon, as there is lots to see. But very often at this time of year the planets might not be out until very late and the brightest thing in the sky is the star Sirius. Problem is, Sirius is just a star and stars appear as just a point of light even when magnified through your telescope. This can be a very boring target and can be disappointing if it is the only bright object. So make certain before you go out for your first night’s viewing that you know what will be up! Most telescopes these days come with some rudimentary planetarium software that can show you what the sky will be like on any night. Failing that there are online websites that do the same thing (sometimes better). Planispheres can also be used, and if you have a Smartphone or pad you should download a planetarium app like Google Sky (its free). Depending on what time of the month it is, the Moon may not be up during evening hours. Since we suggest the Moon as a great first target for your telescope you might want to wait for it. Failing that, try to look for the brighter planets.

6) Got a computerized telescope? Take advantage of free smartphone apps to make it much easier to set up!

We’ve been kind of ‘meh’ about computerized telescopes in the past, and are still a bit wary of a telescope where 70% of the cost is in the computer andGoogleSky motors and not the optics. But we have softened a bit since they have become a bit easier to use – and not because they changed, but rather our phones did.

Computerized telescope makers kind of make it seem like a computer means your telescope will magically find things in the night sky. All you need to do is toss it into your yard and enjoy the viewing. But that is not how they work. To set up the telescope’s computer you need to point it at two named stars so it can calculate where everything else in the night sky is located. This used to mean that to set up the telescope you had to have good knowledge of the night sky to find those stars -which kind of defeated the purpose.

But now smartphones are ubiquitous these days and there are plenty of planetarium apps out there for free that will help you identify those stars. Smartphone planetarium apps are not super-accurate (they can be off by as much as an hour)  but they will help you spot and identify bright stars that you need to aim your telescope at to orient the computer.  This makes the computer orientation much easier to do than trying to learn to use a planisphere or star map on the fly.

7) Learn, learn learn!

There’s a host of information for astronomy newbies on the internet and in books. Amateur astronomers are very keen on sharing their knowledge and experience with you. Check out the major magazines online websites such as Sky & Telescope or Astronomy. There are a zillion astronomy websites with forums as well you might wish to peruse. Even on this blog we have a collection of Telescope Tips you should check out for helpful advice. Also consider joining or at least contacting your local astronomy club – you can find all kinds of help from them, as well as many other benefits from membership (such as loaner equipment).

If your first night with your telescope is a good one, then you’ll have a much better time with the hobby. But always remember a little planning goes a long way!

Happy New Year!

Interested in buying telescopes?

www.spectrum-scientifics.com

5 Tips to use an Telescope with an Equatorial Mount (the easy version)

In past entries in this blog we have discussed the merits Equatorial Mounts vs Altazimuth mounts on telescopes, but we never actually went into much 016detail on how to properly use one of these mounts. Here are some basic hints for a beginner first trying to use an equatorial mount. Note that this are not hints for precision alignment – they are strictly for the beginner so they do not get overwhelmed! Speaking of which

1) Keep you mount setup as simple as possible at first.

Look at telescope instructions for equatorial mounts and you’ll see a lot of information on adjusting setting circles, using a polar axis scope, and other heavy duty details. Here’s a hint: If you don’t plan on doing astrophotography or long, long viewing sessions you don’t need all of that setup! Here is what you need to do:

(more…)

Telescope Tips: Finder Scopes vs. Red Dot (Reflex) Finders

Aiming a telescope is tricky: It sees only a tiny portion of the sky, it might not be in focus for what you are looking at, and slight bumps can throw off your aim. That is why most telescopes come equipped with some kind of aiming device to help you find objects in the night sky. In the past this was almost exclusively with a Finder Scope – a little, low poweder telescope on top of the main telescope’s optical tube with a cross-hair that was used to aim.

FINDER SCOPES

The design of these little telescopes would vary from 20mm to 50mm in diameter, and the power was from 5x to 9x, typically. The holding bracket originally

083

would be two metal O-Rings with three thumbscrews each to adjust the aim of the finder scope. More recently that design would be replaced with a single ring with two thumbscrews and a spring bracket. Those were the good ones, anyway. Cheaper telescopes would often have a plastic 5x finder scope with a single holding bracket with

Not a good sign.

Not a good sign.

three plastic thumbscrews that would often frustrate new telescope owners as this mount is clunk and hard to control and the optics in the finder scope were poor.

This frustration would lead to a buig change in smaller telescopes around 10-15 years ago as they switched from cheap finder scopes to using reflex finders.

 

REFLEX FINDERS

Reflex finders, or red dot finders involve no magnifying optics. Instead the reflect finder has a window that you look through and a red dot is projected to show where the telescope is aimed. Adjustment is made by two knobs. This was much easier to deal with fot new astronomers as the main frustrations with cheap f

080inder scopes were mostly alleviated by using a red dot finder. But unfortunately they were replaced with new issues. The first being that all too often the new astronomer would leave the Red Dot Finder on after the viewing session was over, which would drain the battery. Long term storage would also be an issue as many would forget to remove the battery and they might leak acid onto the electronics.

The final issue was that once the astronomer gains some experience they will not be able to use the Red Dot Finder for a technique that is ued by more advanced astronomers to find objects: Star Hopping. This is where the viewer jumps from star to star in the field-of-view of the finder scope to get towards an object they are seeking such as a small nebula or globular cluster.  The technique involves having one bright known star that is near another known star (not as bright) such that they can both be in the field of view of the finder scope. That 2nd start is then centered in the finder scope and a 3rd star that is near the edge of the field of view is found and so on. It is a tricky technique to learn and unfortunately you can’t do it with a Red Dot Finder.

SO which to choose? Well, some do not:

Why_not_both-

More determined astronomers will actually have both designs on their telescope. A red dot finder to easy aiming along with a larger finder scope for close work and star hopping. This may not be an option for those using smaller telescopes as they have limited space for such extravengance.

Here is a summary of the main points along with some other advntages and disadvantages:

FINDER SCOPES:

Advantages:

  • Have actual magnification
  • Can be used to star hop
  • Magnification gives a  better sense of where you are viewing
  • Can be purchased as ‘right angle’ which makes using them on Reflecting telescopes easier

Disadvantages:

  • Harder to use for new astronomers
  • Trickier to align properly with the optical tube
  • Cheap ones extremely hard to aim
  • Need to keep clean

RED DOT FINDERS

Advantages:

  • Easy to use, especailly for new astronomers
  • Much easier to align with the telescope

Disadvantages

  • Batteries can be drained if you forget to swithc off
  • Batteries can leak in long term storage
  • No magnification means no star hopping

Have fun viewing whichever you use!

www.spectrum-scientifics.com

Updated Repost: So you got a new telescope for the holidays – A Quick Primer for new telescope users.

This is an updated repost of our popular new telescope owner Primer. We’ve added a few bits concnering new attitudes on computerized telescopes and a few other minor tweaks. Be sure ot pay attention when you first use your telescope. Locally, most folks probably haven’t since I don’t think we’ve had a clear night since the 25th.  Anyway, read-on and learn!

So you got a new telescope for the holidays: A Quick Primer for new telescope users.

Be it X-mas, Hannukah, Kwanza, Solstice or Giftmas this is the season for getting telescopes as gifts. Sadly, many of these scopes might be rushed into usage and some critical steps might be 016skipped. This can result in a frustrating experience for a budding young astronomer who may give up their new hobby prematurely. This can be avoided if you only take the time and a few precautions to make certain you get the baby steps out of the way without too much tripping and falling.

1) Do as much as you can during daytime first!

I can’t stress this too much. Many folks assume they can assemble their telescope right out of the box at their chosen viewing spot – in the dark. Suffice it to say this is not a good idea. Assembling out of the box at the viewing site might be an extreme example but you should certainly try working your scope and getting the ‘feel’ for it during the daytime as much as possible. Take your telescope outside during the daytime and point it at a nearby tree or other object (the object should be at least 1/4 mile away). Use this object to align the finder scope (see below) as well as test how the eyepiece focuses. Try changing your eyepieces between the low and high powered ones to see how that works as well. Move the telescope in large movements as well as using the slow motion controls as well. When you do these things in the daylight you can get a much better feel for how they should work than if you try them at night. Also if you drop an eyepiece or loosen a screw you have a decent chance to find it. Get your mistakes out of the way when the sun is up.

2) Assemble your telescope properly

This should go without saying, but it is amazing how many folks skip a few steps or don’t attach parts, or don’t read the instructions properly. We’ve seen telescopes in for “repairs” just after the holidays that were just put together wrong, or some critical final steps were ignored (slow motion controls not attached, counterweights not placed). Most of the time, there are very few non-critical elements of a telescope’s construction. So be sure to follow the assembly procedure carefully. Allow yourself a couple of hours as well (maybe three hours for certain models of dobsonian telescopes) for the assembly. Don’t assume you can just put it together a 1/2 hour before you plan to head out and view.

3) Align your finder scope. Align your finder scope! ALIGN YOUR FINDER SCOPE!

Get the point? Many folks ignore this step until the last minute and we can tell you that trying to work a telescope without an aligned finger is very,very, very hard. Even the lower 084magnifications on a short focal length telescope only see a little under 1 arc degree of the sky. This is a tiny portion of the sky so hoping to find an object with just the eyepiece is really hard to do. There is a reason why almost all telescopes come with a finder scope. So make sure to align it (During the daytime per suggestion #1) . If your telescope comes with a red-dot finder instead of an optical finder scope, be certain to carefully align that as well during the daytime – and don’t forget to switch it off! A dead battery in a red dot finder is nobody’s friend.

4) Did you get an Equatorial mount? Figure out how it moves!

An equatorial mount has some great advantages over a regular altazimuth (altitude-azimuth) mount. It can track, be motorized, and the larger ones can even be used with setting circles to locate objects in the night sky. But these are only true if you take advantage of the equatorial mount’s features and set it up properly. During the daytime (suggestion #1 again!) try a rudimentary set-up of the equatorial mount. This does not have to be super accurate as some telescope’s instruction manuals may require, just enough to get mostly accurate tracking for a little while. Perhaps more importantly, get a feel for how the telescope moves – you are used to moving things in an up/down left/right fashion. Now you need to get used to moving the telescope in declination and right ascension. Try moving the telescope from one target to another using the mount properly during the daytime to get a better sense of it. One thing to keep in mind is that the counterweight is there for a reason – it shouldn’t be pointing down all the time.

If you have a larger Equatorial mount keep in mind that you can use the setting circles to help find objects in the night sky with the help of a star atlas. But this means you have to learn to use it. Read your instruction manual carefully. You might also consider downloading a Sidereal Time app for you smartphone. You’ll see why once you figure out the details of using your Equatorial mount.

5) Choose your first targets wisely!

Many folks go out with their telescope and just point it at the brightest thing in the sky. This is fine if the brightest object is a planet or the Moon, as there is lots to see. But very often at this time of year the planets might not be out until very late and the brightest thing in the sky is the star Sirius. Problem is, Sirius is just a star and stars appear as just a point of light even when magnified through your telescope. This can be a very boring target and can be disappointing if it is the only bright object. So make certain before you go out for your first night’s viewing that you know what will be up! Most telescopes these days come with some rudimentary planetarium software that can show you what the sky will be like on any night. Failing that there are online websites that do the same thing (sometimes better). Planispheres can also be used, and if you have a Smartphone or pad you should download a planetarium app like Google Sky (its free). Depending on what time of the month it is, the Moon may not be up during evening hours. Since we suggest the Moon as a great first target for your telescope you might want to wait for it. Failing that, try to look for the brighter planets.

 

6) Got a computerized telescope? Take advantage of free smartphone apps to make it much easier to set up!

We’ve been kind of ‘meh’ about computerized telescopes in the past, and are still a bit wary of a telescope where 70% of the cost is in the computer andGoogleSky motors and not the optics. But we have softened a bit since they have become a bit easier to use – and not because they changed, but rather our phones did.

Computerized telescope makers kind of make it seem like a computer means your telescope will magically find things in the night sky. All you need to do is toss it into your yard and enjoy the viewing. But that is not how they work. To set up the telescope’s computer you need to point it at two named stars so it can calculate where everything else in the night sky is located. This used to mean that to set up the telescope you had to have good knowledge of the night sky to find those stars -which kind of defeated the purpose.

But now smartphones are ubiquitous these days and there are plenty of planetarium apps out there for free that will help you identify those stars. Smartphone planetarium apps are not super-accurate (they can be off by as much as an hour)  but they will help you spot and identify bright stars that you need to aim your telescope at to orient the computer.  This makes the computer orientation much easier to do than trying to learn to use a planisphere or star map on the fly.

 

7) Learn, learn learn!

There’s a host of information for astronomy newbies on the internet and in books. Amateur astronomers are very keen on sharing their knowledge and experience with you. Check out the major magazines online websites such as Sky & Telescope or Astronomy. There are a zillion astronomy websites with forums as well you might wish to peruse. Even on this blog we have a collection of Telescope Tips you should check out for helpful advice. Also consider joining or at least contacting your local astronomy club – you can find all kinds of help from them, as well as many other benefits from membership (such as loaner equipment).

If your first night with your telescope is a good one, then you’ll have a much better time with the hobby. But always remember a little planning goes a long way!

Happy New Year!

Interested in buying telescopes?

www.spectrum-scientifics.com

 

 

Telescope Tips: When Buying a telescope, Don’t ask “How Far Can I see?”.

We’ve sold a lot of telescopes to beginning astronomers, and one question that gets asked almost every time is: “How far can I see with this telescope?’.

Sadly, this is not the right question to ask.  Let me explain:

There are objects in the night sky that are a million light years away, such as the Andromeda Galaxy that are visible inAndromeda even small telescopes. To put that in perspective, you can see an object that is over 6,750,000,000,000,000,000 miles from us and yet a small 60mm refractor telescope can view it given clear skies and low light pollution. The reason? Well, it is a galaxy, made up of over a trillion stars. It’s big. Real big, and fairly bright too, given how far away it is.

By Comparison, take the dwarf-planet Pluto, which despite its recent demotion is still a resident of our solar system. At its closest, Pluto is 648,000,000 miles from Earth (it varies – a lot) How visible is Pluto? Well look at the image of Pluto taken by one of our most powerful telescopes: the Hubble Space Telescope:

pluto1As you can see the image is not very impressive.

This standard applies in real life. If you ask someone ‘how far can you see’ when viewing on Earth you won’t get a real concrete answer as well. See what? Exactly. You could probably see a skyscraper from miles and miles away. But ask to read a street sign from two blocks away and you will be hard-pressed to even spot the sign, let alone read it.

A perspective on distance can be found in the excellent cartoon XKCD, which has a comic about distances here, using a logarithmic chart. We had this question put to us so often that we ended up buying the poster to explain to customers how the Universe is sized.

So the question that should be asked is not ‘how far can I see’ but rather ‘what can I see’ with the telescope.

In answer to that question we find that at a minimum a telescope, even a small one, should be able to view:

1) The Moon, with sharp details of the craters

2) The phases of Venus,

3) Mars, without much detail

4) Saturn and its rings

5) Jupiter, with a hint of its banding as well as the Galilean satellites

6) Neptune & Uranus, with only minimal details

7) The brighter Deep Sky objects, such as the Orion Nebula, Andromeda Galaxy & so on, assuming conditions

Now keep in mind when we say ‘view’, we mean view with some clarity, and some ability to recognize the object. Any cheap telescope can see Saturn, but if it just an amorphous blob through the cheap lenses what good is it? You should be able to identify that it is in fact a planet with rings around it. It might look like a cartoon of an eye, but it will obviously be Saturn.

Now of course, as you improve the quality of your telescope (namely, increase the aperture of the lens or mirror) the image of these objects will increase as well. Saturn will go from being that carton eye to actually having some more details, and eventually you might make out the Cassini Division (the major separation of Saturn’s rings). Jupiter might have more bands become visible. So on and so on.

So the real question(s) should be “What can I see and how well can I see it?”

www.spectrum-scientifics.com

 

The 6 signs of a bad telescope.

There are a lot of telescopes on the market, and not all of them are good. Sure, a good percentage of them are decent telescopes and even some of the weaker entries might be good enough for 90% of people’s basic viewing needs (such as of the Moon and Bright Planets). But there are a lot of telescopes that, even if functional, are simply not worth the money you pay for them. Here are some of the of warning signs of a bad telescope that you can determine without having to do full optical analysis:

This is actually not one of the worst offenders we have seen.

This is actually not one of the worst offenders we have seen.0

1) Large magnifications listed on the box!

You’ll see this on a lot of department stores – they list huge magnifications on bright letters and those numbers are mighty big for a small telescope. Numbers like “640X” or “1280x” a all over the box, trying to impress the customer.

Fact is, a telescope, no matter how well made, should not be magnifying more than 50x per inch or 2x per millimeter of aperture. This is why advanced astronomers use bigger, wider telescopes.

(more…)

The Art of Surviving an Astronomy Session

So you got yourself a new telescope and it is a clear night out. Time to grab the new telescope and bring it outside, right? Hold on there; as many new astronomers have discovered, an observing session isn’t as simple as when you go outside in the winter/early spring to put out the trash. There are several things you should probably prepare before you go out for a night of observing.

DRESSING FOR THE NIGHT WEATHER

Far, far too many folks dress for the daytime weather. This can be a problem for you if the daytime was a happy 78 degrees and then drops as the sun goes down into the 60’s.  Many an observing session has been ended prematurely because the astronomer forgot to wear a sweater.

For colder weather, it is 670px-Dress-for-the-Cold-Step-1-Version-2wise to dress in layers.  This way you can adjust your level of warmth as the night goes on. The only trouble with dressing in layers is that you need to get dressed indoors where it is warm and putting on multiple layers is a bit more complex than just tossing on a jacket. I have had sessions where I dressed for warmth and then had something delay my exiting the house, the result being me sweating up a storm before I got outside.

PREPPING THE AREA AROUND THE TELESCOPEfoldingtable

Even if you only have the eyepieces that came with your telescope and a star chart it might not be a bad idea to have somewhere to put these items down. A simply folding aluminum table can help a lot without being too much of a burden. You might also consider some kind of carrying case for the eyepieces. Keeping them in your pocket can be hard on the glass and coatings in the long run.

KNOW WHAT YOU WANT TO VIEW IN ADVANCE…OR DON’T

2241largeWell before you go out, you should decide what you would like to observe that night, or if you just want to aim the telescope around and see what you can find. The latter can be lots of fun, but it can also get old pretty fast if you don’t find anything of interest. The former does require some planning, so be sure to check your planisphere, planetarium program or other astronomical assistant before going out.

HAVE FUN!

Far too many folks turn hobbies into chores – Astronomy is by no means unique in this regard. Doing some work in any hobby to get the most out of it is to be expected, but turning it into a huge burden can make you burn out on astronomy.

www.spectrum-scientifics.com

 

 

 

 

 

Astronomy Hints #18: Do I need a red light flashlight?

There are many factors that can effect the quality of a telescope session: clouds, turbulence, haze, light pollution, moonlight, and so on. Most of these the astronomer cannot do anything to change, but one of them – night adapted vision, you do at least have some control over. You cannot control everything your eyes do, but you can help them a lot.

Many beginning astronomers often make a common mistake of going from a brightly lit house with their telescope out into the darks skies and start viewing through their telescope immediately. This can be a bit unsatisfying if you are looking at dim deep space objects. The will be extremely faint simply because your eyes are not adapted to the darkness. This isn’t just about the pupils of your eyes dialating, either. (more…)

Astronomy Tips: Astronomy Smart Phone Apps Part 2

OK, so in Part 1 we covered 4 different astronomy/telescope apps for your Smart Phone.  In part 2? Well, we’re going to pretty much do some more of that.

ZoomCalc

ZoomCalc

ZoomCalc is a simple program where you can input stats from your telescope to get some interesting optical information about your telescope. The program has 2 parts, 1 for your telescope and one for the eyepieces. The first you need to enter the aperture, focal length, and eyepiece size (1.25″ or 2″). ZoomCalc then presents a screen of information about what your telescope can deliver:

Zoomcalc1

Sorry, the only screenshot we could find was in Cyrillic. But suffice it to say you are provided with 12 optical aspects of the telescope from Maximum magnification, aperture ratio, and many others. If you don’t know what the terms mean there is a handy pop-up button that gives you a definition. Mind you all of these results be be had with a calculator but its handy to get them all at one shot.

The eyepiece part is a bit useless. It just calculates magnification, something anyone should be able to do with a calculator or in their head. An app like this should have gone the extra step and figured out apparent fields of view and such. It would have been much more useful.

Verdict: Handy for experienced astronomer, but not critical

Next Up: Telescope Calculator Lite

telescopecalclite

This is a lot like Zoom Calc but does both more and less in the same time. With Telscope Calc Lite you enter your telescope’s aperture, focal length and the eyepeice’s focal length and apparent field. From this Telesceop Calc gives you some handy calculations:

telescopecalclite1

There is more about fields of view and such with this app, but unlike ZoomCalc there is no explanation of the terms. The help pages gives some hints but not a true definition. This is designed for astronomers who already have knowledge of such terms and just would rather have an easy way of calculating rather than trying to remember the formula for true field.

Telescope Calc Lite has a nice night mode you can toggle from the menu. Handy.  The ‘Pro’ version of this app costs $0.99 and lets you save values you have entered.

Verdict: Handy for astronomers with some experience.

Next: Meteor Show App for Android

meteorshower

Meteor Shower App is pretty straight forward. You open it up and it shows you  a list of all the major meteor showers for this year and the dates they take place. So that you can settle bar bets the ones that have already passed are not removed from the year’s list:

meteorshower1

Clicking on a shower listing gives you more handy details such as the phase of the Moon during the peak, more dates, hourly rate, and a few more details.

Note that there is a similar app for the iPhone that is actually a bit less crude looking than the android app:

Meteorshowerappiphone

The only things is that the Android app is free while the iPhone costs $0.99

Verdict: Good to have!

Next: Telescopes Demystified

teledemyst

This is available for the Android only.

This isn’t really an app, its more of a book about astronomy. A very limited book..and really probably not a very good book. We can start with the fact that the app is called telescopes demystified and then has Telescopes Mystery on the pic and ‘cover’.

The book is divided in to chapters and there is not much rhyme or reason to how they are laid out. Radio telescopes are mentioned, some odd reviews of telescope that made me go ‘really?!’. Only some limited info about actually using your telescope and some chapters just seem like outright ads for telescope models and companies. I tried to evaluate this for someone who was brand new to astronomy and all I can say is: you can do better. Hordes of websites from amateur astronomers do a better job, our own telescope buyer’s guide does a better job. You can get a lot more info than this ‘book’ from wikipedia. I just was not impressed overall.

Verdict: Don’t Bother

www.spectrum-scientifics.com

 

 

 

 

 

 

Astronomy Tips #17 – Salvaging an old telescope

We hear this story quite often:
“I was going through my old room at my parents house and I found my old telescope! I hadn’t seen it since I was twelve! I wonder if it still works?”

“My father passed away, and I found this old telescope in his belongings, I never knew he had one. Can it work?”

” I was at a flea market and I picked up this telescope for just $20. Its missing a few parts, I think, but I wonder if I can get it working?”

” We bought a house and while cleaning it out we found this telescope. I wonder how good it is and if it will work?”

“I bought a lapse storage unit in an auction and one of the things inside was this telescope. How much is it worth if I clean it up?”

It isn’t a daily event here at the store, but it sure does happen a lot. People find/refind/salvage an old telescope and they want to know if it is a)valuable or b)can be made to work again.

The short answers to those questions are a) Probably not and b) maybe, but is it worthwhile?

Here’s the facts: almost 90% of the telesco0pe we see brought in to the store are small refractors. They are usually older versions of something like this Orion Observer 60.

Small refractors make up a huge portion of telescope sales today, especially for beginners, and it was no different 10,20, 30, or 40 years ago. They are usually the least expensive models available and were sold in camera shops during the holidays – larger telescope you usually had to send away as mail-order. These small refractors had company names that often are not around anymore: Jason, Telestar, Bauch & Lomb, and so on. Now you may notice from the link above that the Observer 60 has a price of just under $100. Remember that number because as your telescope get repaired it is going to cost money – and at a certain point you might think that maybe getting a new telescope is more economical than repairing an old one.

Still, let’s break this down into different categories of problems:

Unsalvageable – At one astronomy club’s star party I once saw a visitor who had brought his old telescope for the club members. When he tilted the end to the ground the lens fell out – followed by a pint of rust flakes. This was a pretty cut and dry case, but in some cases it might not be so obvious what is unsalvageable.

1) Bakelite telescope bodies – I’d be amazed any telescope with this kind of body survived as long as it did.

2) Plastic telescope bodies – These can vary a lot. Some are actually decent or even ABS plastic. But the models with cheap colorful plastic aimed for very little kids are usually not worth saving.

3) Damaged Tripod legs – The shift in low-cost telescopes from wood legs to aluminum legs only took place about 12 years ago, so most old telescope often have wood tripod legs. Wood is fin but it can warp from moisture or splinter from pressure. If there is damage to the legs or the bracket on the tripod legs odds are it is not worth repairing.

4) Missing main lenses or mirror, missing eyepieces are one thing (see below), but if you telescope is missing the main lens/mirror it will not be worth saving.

5) Bends in the tube. Dents are one thing, a telescope with bent tube simply is not going to work.

6) Rust – usually only happens with reflectors, but rust inside the tube is big trouble. Outside is no so big a deal.

Needs Parts – Most old telescopes are physically just fine but are just missing a few things. Telescopes often have lost the little things that came with it, such as the eyepieces. This is a problem as the eyepieces are need for the telescope to work. The good news is that you can often buy these parts – but it might get harder to do so in the future.

1) Eyepieces – second only to missing diagonals, eyepieces are usually what most found telescopes are lacking. This is not too much of an issue as you can usually buy new eyepieces. Trouble is, when they run $20-30 per eyepiece you use up a lot of that ‘$100’ figure we mentioned earlier.

Another issue with eyepieces is the size. Times were most low-cost telescopes were made in Japan and used eyepieces that had a .965″ (25mm) barrel diameter. The US standard was 1.25″. As time went on and manufacture of low-cost telescopes was moved to Taiwan and then Chine the US standard was used more frequently. This is good as people buying a new telescope  have a better design, but it also means that there is less reason to make the smaller lenses. 10 years ago the major telescope suppliers made decent design .965″ eyepieces. But the need for them dried up with the old Japanese models so they stopped making them. If you cannot find .965″ eyepieces you may need to use and adapter and US standard eyepieces.

2) Diagonals are probably lost more often than the eyepeices. They have the same sizing issues and unfortunately can be harder to find than eyepieces in the .965″ standard.  Some telescopes can still come to focus without their diagonal, but some cannot.

3) Finder Scope – While lacking a finder scope does not make the telescope useless, it does make it much, much, much harder to use. Usually most old telescopes had a cheap, plastic 5x finder that are difficult to adjust. A LED reflex finder is a much better option, although you may have to buy it and a bracket to attach it.

4) Dust caps – Without dust covers your optics will likely accumulate dust and grime. If these are missing you might want to improvise something as they will be hard to replace. A clean cloth held on by a rubber band can work for short term storage of a telescope.

Mechanics – Things fall apart, but they can often be repaired.

1) Small dents and dings – these usually won’t affect much. Even the most severe dent a tube can take before bending is not likely to block the light path.

2) Tripod parts go missing. Some of these can be lethal to the telescope’s recovery. Brackets that are attached to wood tripod legs can bend or break and are not worth repairing or replacing. On the other hand, often what gets lost are thumbscrew and bolt systems that attach the tripod leg to the accessory tray that keeps the legs properly sturdy. These can usually be replaced at a local hardware store for a small amount.

3) Stick legs. Wood swells. Sometimes it bends but often what happens is that the center portion of the tripod leg swells up and can’t be adjusted. You may need to use some strength to get it loose again and it may require some sanding or grease. No cost to fix this, however. If the swelling results in bent or broken legs, however, you are back into the unsalvageable category.

Optics Cleaning – Unless your telescope was sealed in a box it is likely to have some dust on its optics, or worse.

1) Dust.  This can be blown off with a rubber ‘blower bulb’. It is important to clear the lens or mirror of dust if it needs more cleaning in any case.

2) Grime, etc. Lenses can be cleaned with the proper lens cleaning fluid. Look for optics cleaning fluid that is suitable for optical coatings. Don’t use window cleaner.  Be sure to use optics cleaning tissues as well as using household tissues and paper towels can damage the lens and coatings.

3) Mirrors with grime. These need to be cleaned, and here are some instructions on how to do so.

This list is by no means comprehensive – the number of things that can be wrong with an old telescope is enormous. But it does give you a sense of what the costs and efforts would be for salvaging an old telescope.

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