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I bought my first telescope, now what…

I bought my first telescope, now what…

by George Fanthome (gfanthome@hotmail.com)

Well ahead of you lie endless hours of pleasure and frustration…. hopefully more of the former than the latter, especially as time goes by and you become more acquainted with your new hobby. I remember the time when I first took the plunge and bought my first telescope. After much deliberation, I decided to go for a 'real' telescope and bought a Celestron 4" (102mm) HD refractor (I say real because at that time my concept of a telescope was a refractor) . When I finally picked up the package, I couldn't wait to put it together and go outside and see all sorts of wonderful things. I think that first night I saw a few stars, didn't know what I was looking at and couldn't find most anything like the planets. I did have a book with some star charts but I didn't even know where to find the constellations. I especially remember a night a few weeks hence when very determined to see something, I set out to see the three prominent clusters M36, M37 & M38 in Auriga. I spent 3 or 4 hours in temperatures below freezing try to locate these from my suburban patio in CT. I did finally see them and felt elated at doing so but was also a bit concerned. If this was how it was going to be, I didn't know if I was going to stay in the hobby very long. Well I'm still here after almost 4 years and have since moved on to, first, a 6" MK67 and then a home made 12.5" truss Dob (I think its called aperture fever) Along the way things have become easier since that cold winter night, in large part thanks to a few things I have picked up along the way, either by accident or by the kindness of the fellow astronomers who make up this great community.

I will try and share a few of these 'gems' with you, which I wish I knew when I first started out.. Hopefully it'll make your experience with this wonderful hobby a little less frustrating and release its potential to inspire awe and amazement. You might have discovered some or most of these things yourself by now or perhaps not.

a) Invest in good quality eyepieces & diagonal:

I am assuming you have gone through the involved process, perhaps agonizing at times, of choosing a telescope and are the proud owner of a wonderful telescope. One of the most important things you can now do is invest in a few good quality eyepieces and a diagonal if your telescope needs one. These make up to 50% of the optics in your telescope. So it is very important that you have eyepieces that can do justice to your telescope. You need not necessarily buy the most expensive 2" wide field eyepieces, although they are, in my opinion, worth it. Some good quality 1.25" plossl will get you well on your way. Orion, University Optics, Televue, Celestron and Meade are all good name brands to start. The choices are many and all vary in what they offer and their price. By and large you get what you pay for. You will find lots of reviews on this website, and others, of all kinds of eyepieces. So look around before you buy.

You will probably need at least three eyepieces - one low power 'finder/Deep space' eyepiece in the 26mm-40mm range, one in the medium power 12mm-25mm range and one high power eyepiece in the 4mm-11mm range. Where in the spectrum your eyepiece falls depends on the focal length of your telescope. A quick way to find out the magnification of the eyepiece for your telescope is given by the formula : Focal length of you telescope (mm) / focal length of the eyepiece. You will need something in the 50x, 100x and 150x range. Also, get the eyepieces, which give the widest apparent field of view and are within your budget. As you get more into the hobby and are sure you are going to stay the course (or have lots of disposable income), you can/will upgrade to the more exotic eyepieces like Naglers, Panoptics, Pentax XLs etc. Opinion varies far and wide as to what constitutes an ideal eyepiece set. I don't think anyone will ever be satisfied with what they have and trust me you will go through a few before you find some keepers.

The same goes for a diagonal. It is very important you get a good quality diagonal like a Televue or Orion or University Optics. These generally are well collimated which is very important.

B) Some Basic books/atlases:

These are indispensable for finding your way around the night sky and learning the finer points of astronomy. You probably already have a few which focus primarily on equipment like Starware or Backyard Astronomers Guide. The following focus mainly on the 'software' side (not to be confused with computer software, which is also available to generate star charts) and should get you started on a basic collection for observing -

- Nightwatch (Terence Dickinson): My all time favorite. It is an all round book. I love its deep sky star charts and seasonal all-sky charts. Although the star charts don't go very 'deep' they are excellent for the more common and visually exciting objects. The charts also have some information about the object like visual magnitude, if it is visible in binoculars, distance, type of object etc. I find it very useful to have this all in one place. Most other atlases / books will make you look else where for all this information. Having everything on one page while observing is very convenient.

- Turn Left at Orion (Consolmagno & Davis): another excellent book covering the Moon, planets and nearly 100 of the most prominent objects. It covers what to look for through the finder scopes and how the object will look at different powers with easy to understand, non-technical description. The sketches of how the object looks through the eyepiece makes it easy to identify, something, which you will find very useful, trust me. Personally, when starting out, I didn't know if I was looking at the right object. Having this type of a sketch versus a full color 20 frames CCD composite image taken with 3 different filters will show the object, as you will really see it. As you might already have discovered there is a lot of difference!

- Messier Marathon Field Guide(Pennington): Very useful even if you are not running a messier marathon, indispensable if you are. Again, finder scope views, drawings at the eyepiece and hints on how to locate the object make this an excellent companion on any night. I find the observing techniques discussed in this book quite useful.

- The Cambridge Star Atlas (Tirion): A very handy star atlas from the master Will Tirion. Shows stars to about mag 6. I didn't find this (or any Atlas) very useful initially. I think this was because of the absence of constellation outlines (since I was not very familiar with all the constellations). This is easily remedied by drawing the outlines yourself and makes the atlas much more useable for the beginner, IMHO.

- SkyAtlas 2000 : Now we are getting serious ! Although some might argue its not necessary for the beginner, and I agree. It's a wonderful star atlas and something you should consider getting at some point (reviews available on this site). Beside the accurate and comprehensive star charts, the clear acetate sheet with Telrad finder circles make this my favorite when trying to find a difficult (speaking for myself) object. This enables one to orient the Telrad correctly relative to a nearby bright star and estimate the objects position. I can't tell you how many times I have found an elusive object using this technique.

- The Night Sky Observers Guide, Vol. 1&2 (Kepple & Sanner): Again, might be a bit much to start with but a great collection of observation reports. Covers objects by season/constellation (64 constellation) and gives descriptions of what would be visible and its appearance in different size telescopes scopes. Most other books only describe what is visible using small aperture telescope while many of you might have started with 8"-12" (or larger) Dobs. Although these also have finder charts and photographs, it's the 'observation reports' and the drawings at the eyepiece through different size telescopes that make these a great set.

There are many more books like 365 Starry nights, The Bright Star Atlas and so on, but since I do not/have not owned these, I cannot say anything that is not already available at Amazon.com or elsewhere. You will be able to find other recommended reading lists on the web.

c) Get a Planisphere:

This is another hard learnt lesson. It makes finding constellations and the more prominent object so much easier. There are all kinds available. You can even use the ones, which come out each month in the popular magazines like Astronomy or Sky & Telescope.

d) Your most important accessory a 1x finder: like a Telerad (best) or a red dot finder.

If you take away only one thing from this article, this should be it. I can't tell how useful you'll find this.

I struggled for a long time with finders, upgrading from the standard issue 6x30 to a 8x50 to a 9x60 in search of finder Nirvana. Accidentally I came upon a Telerad. I don't use a high power finder any more.

- Telrad: The original and the best. It consists of a bulls-eye target of concentric rings illuminated by a variable intensity red led, and is viewed while looking up the scope tube with both eyes open. It makes pointing your telescope a cinch and finding your target becomes much, much easier. Take a look at http://www.company7.com/telrad/products/telrad.html . It's a good article on the Telrad and gives all the specs etc. A lot of the Star Atlases and charts are designed to work with a Telrad, which is an added advantage.

- Rigel Quick finder: Similar to the Telrad but has a higher profile and is much lighter. If you have a ST80 or similar refractor or even a Newtonian/Dob you might find the higher profile of the Rigel quick finder more convenient. The downside is that the circles projected are of a size different from the Telrad. If you are planning to use a star chart, which has a template for a Telrad (see SkyAtlas 200 above), it might not w- Red dot finders: Quite a few companies make these like Orion, Celestron, and Televue etc. These project a single dot at 1x magnification. The advantage is the small size and lightweight. The disadvantage is that the dot might be covering you target (minor), the profile is typically very low so looking through these might not be as easy.

e) Higher power finders:

If you still feel you need a magnifying finder, I would suggest getting a correct image, right angle one. I believe Antares makes a good one. It'll be worth the money. In any case get at least a 7x35 or better still an 8x50. Quality is everything in these types of finders. Some people swear by their Takahashi or Vixen finders but they can cost almost as much as a beginners telescope. Not necessary to start with IMHO, especially if your eyepiece/telescope can give you 1.5*+ views.

f) Get a rest (chair): or some sort of support.

It makes a lot of difference and will keep you going for hours without getting exhausted. For a long time I observed without one. Then I finally gave in and made myself one (a quick and dirty project which took about 3 hours over a couple of days). I wish I had gotten one earlier. I usually get so lost in observing that I don't feel the effect of the physical contortions I go through then. It's only when I am packing up or later the next day that I will discover/rediscover new muscles that I never knew existed. Besides the physical comfort, it actually makes a difference in what you see. It's said a good rest adds a magnitude to what is visible at the eyepiece. I have found this to be true.

g) Help on the web:

since you are reading this article, you probably have access to the Internet. There are a lot of web sites and news groups that provide excellent help/articles/reviews. Take some time browse around. I would recommend that you never buy anything without reading the reviews available (I am pretty sure if it is exists, it has been reviewed somewhere on the web!). My personal favorites are:

  1. www.scopereviews.com : Ed Ting's site has been my first stop whenever I am buying astronomy stuff. I trust his reviews and will almost never buy anything without checking out this site.
  2. www.cloudynights.com : I discovered this site sometime after the above. Now these two are my top two sites. As you will find, this site has lots of reviews & articles written by the astronomy community for the community. My thanks go out to Allister for providing this forum/web site.
  3. www.weatherman.com : Another excellent site with lots of reviews.
  4. http://www.excelsis.com/vote/astro/ : Excellent site with rating given by Astronomers themselves.
  5. Look at www.egroups.com or http://groups.yahoo.com/ : you can search for the astronomy news groups and you will find a lot of them. You get help here by posting your questions or even just by browsing the archives.

h) Join a local club:

you must have heard this before. Do it if you can. There is no substitute for a seasoned hand to show the ropes. You will find the local club members very willing and able to help. Plus its fun (and safe) to observe with others. Some of the best observing sessions I have had are with two of my friends, Michael and Glenn.

i) Basic telescope/eyepiece maintenance:

you shouldn't have to do this very often but perhaps once a year is warranted. Be very careful. Read the owners manual. Read articles on the web. The most important 'maintenance' or 'setup' you can do is collimating your telescope. Of-course keeping the lens/mirrors of your eyepieces and telescope is important too but unless they are totally goo'ed up they won't affect your viewing to the extent a badly collimated telescope will. Collimating a telescope can be a daunting task if you are just getting started. The degree of difficulty / complexity also depends on the type of telescope you have. Reflectors are relatively easy to collimate while Cassigrains can be more difficult, while some refractor may not even allow any collimation (most good ones will). But don't let this deter you; having a well-collimated telescope might just be what keeps you from selling the telescope you have. My suggestion to you would be to seek help at your local club if you can. Get one of the members to show you the ropes. There are articles available on the web on how to do this. Also, if you buy some type of collimating tool like a laser collimator, or a Cheshire tube, they will come with some form of instructions (as might your scope).

When I first started I had no inkling what collimation was. I was not at all satisfied with my first telescope and I though it was because of its 'small' aperture (4" C102HD refractor). While could be partly true, looking back I feel the scope was not optimally collimated. I ended up selling the scope to get a bigger one. For a long time I was not satisfied with this either, again because I though the 6" aperture of the MK67 was the reason. So I started making a 12.5" f/5 truss Dob. Along the way I learnt a lot about telescopes, optics and collimation. I went back and collimated my MK67; it made a whole lot of difference. Perhaps I would have not moved onto the 12.5" if I had the MK67 collimated earlier. Then again, perhaps not. As my good friend the Dr. (Glenn) says, 'It's a great hobby or what?' There is always something new to learn, something new to try. One thing is for sure; your first scope will not be your last.

By no measure is the above comprehensive. In all likely-hood, I have missed some things, which might be of help. Also the above are my personal opinions, experiences and preferences. Everyone eventually arrives at what is 'essential' for him or her. Besides this there is a lot more out there, so the one thing you need not feel is that you are alone in this hobby. I have found the Amateur Astronomers community to be made up of some great people who are always willing to help. I hope you find this of some help in dealing with some of the initial frustrations. Stick with it; it will get easier.

I wish you luck and happy viewing.

  • Joeman25 and PLeocorny like this


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