When I finally discovered my interest in astronomy observing I knew immediately that I wanted a telescope of my own. The possible selections of what to buy were almost endless. Since it was an entirely new hobby to me I wanted to make sure I would stay with it long enough to justify the expense of a telescope and that whatever scope I chose would be something I could and would use. But in reality, you don't know initially if you will develop a longtime interest in the hobby. That puts you in a slight delima at first but in my case there was a viable solution. That solution is what I want to discuss in this article about how to avoid buying the wrong telescope.
The telescope that I was looking thru when I really got "hooked" was a 20 inch DOB that a professional observer from the Mcdonald Observatory at Ft Davis, Tx was using to teach a two night astronomy session to a bunch of folks who were on a activity planned vacation. For those of you that don't know much about scopes, that's a "REALLY BIG ONE". You had to climb up a ladder to look into the eyepiece and the instructor had to continually keep adjusting the scope to keep the desired targets centered. No matter what the difficulty was, the view of the Andromeda galaxy thru that eyepiece was simply mind boggling to me. I knew right then that I wanted a telescope. At the time a scope like that would cost somewhere in the vicinity of $2500/$4000 dollars. A whole lot more than any beginner should even consider investing in a hobby that might or might not be a long lasting one. I needed an avenue to find a scope that I could use that would be both economical and functional. For me that avenue was to begin reading articles in Sky & Telescope magazine and join a local astronomy club. It was a full 1 1/2 years before I made the decision to actually buy a telescope. Not that I had wavered any in my desire to own a scope but for me I wanted it to be one that I could use and actually see the objects of interest in the sky.
The first scope that got my eye was a Meade 4 inch computerized telescope that you could use on a tripod or sit on the top of a table. It was small, easily transported and that computerized mount sure looked inviting to me. I wouldn't have to know very much about the night sky to be able to see things using that baby. At least that is what I had in mind. I must have looked at that scope in a dozen or more telescope shops over the course of that 1 1/2 years. It could be purchased for somewhere around $400 dollars. A 4 inch mirror is a fairly small mirror for a reflector scope and I knew that the larger a telescope mirror was (basically the size of the telescope) the more light it could gather, hence the more potential there was to see more things. I wanted a scope with the largest mirror I could afford to buy. Finally, I set a top price that I felt that I could spend and that opened several more options to me and closed other options. Any type of computerized scope larger than the 4 inch model would be well beyond my dollar allowance so that pretty much ruled out a computerized scope for me. Additionally by this time I had come to realize that for me learning the night sky and how to find objects by manually searching for them (of course aided by charts etc) was a part of the hobby that I wanted to develop. So it was back to the catalogs to find a scope that would meet all those requirements.
I settled on an 8 inch reflector that was on an equatorial mount. I must confess here that my memory does not tell me why I decided on the equatorial mount other than to note that once properly aligned and the target located you can track the target with the simple rotation of a guidance knob on the mount. There are a few other details to observing with an equatorial mount but I won't go into those here. In April 2000 I set down in front of my computer and ordered a Orion 8 inch scope. It cost me about $200 dollars more that the 4 inch would have and about $300 more than a small DOB I was considering. That 8 inch scope served me well for a couple of years and I still have it. However, after a couple of years of observing I decided that a DOB type scope would be more suited to my observing habits. All astro observers fall prey to the "larger scope" syndrome sooner or later and I was no exception. I also discovered that the hobby of star gazing was really something I liked to do so I was willing to spend more money to satisfy myself. It wasn't long until I plunked down about $800 dollars and became the proud owner of a Meade 12.5 inch Dobson scope.
That bigger and better scope for me was still a reflector scope but it was on a Dobson mount. Most often these scopes are simply referred to as "DOBs". For simplicity purposes, think of a DOB as a tube that sits on a lazy susan so you can push and pull it where ever you want to point it with almost no effort. Generally speaking, a DOB with a solid tube to house the mirror is just that---a tube and a base mount. Two pieces and that is it. Because of the simplicity of the design, the scope is much less expensive than any comparable sized scope with a different type mount. It is by far the easiest scope to use because you simply push or pull it toward the desired target. However, you must constantly make small adjustments to the scope because it doesn't track the desired objects automatically. Don't be misled here---with any non computerized mount, regardless of type, you are going to have to know the sky above you if you are ever going to find things to look at.With all the simplicity of the DOB, there are things that you must consider. Weight and the length of the tube assembly are the major factors. A solid tube 16 inch DOB can easily weigh up to 100 lbs and the base can weigh about 75 lbs. The tube can be 6 feet or longer. Lugging that kind of weight around on an observing site can be a little intimidating. But where there is a will there will always be a way and this is no exception.
By this time, (about 2008) I was really into the observing thing and the desire for a larger, truss type began to enter my mind. A friend of mine happened to have a 15 incher and offered to trade it to me for my 12.5 incher and a few $$$$ to boot. It was a deal I simply couldn't refuse. That scope was just what the Dr. ordered and it seemed perfect for me. Not to big to move around but big enough to really see and observe deep sky objects. Then it happened again. Another friend offered to trade me a 20 inch Dob for my 15 because the 20 was getting to difficult for him to move around. And the offer was for an even swap!!! The temptation to move up to a large scope without spending more money is worse than offering candy to a baby.
I was now on my fourth scope ( notice that all were DOBs except the very first one). The larger scope proved to be as much more impressive as each one of the previous upgrades I had made but I soon discovered why my "FRIEND" was so eager to trade. I had finally got to the point where I couldn't load and unload the base of the larger scope without someone to help me. But I wasn't about to part with that large scope. I would either have to revert to taking the smaller 8 inch scope I had originally purchased to star parties away from my house or just not take a scope . Neither of these options made me feel very good.
Suddenly out of nowhere my benefactor appeared in shining armour. Lucy stepped up and asked the key question---"WHY DON'T YOU BUY A SECOND DOB THAT YOU CAN EASILY HANDLE AND MOVE EASILY IN THE PICKUP?" How she ever discerned my thoughts I will never know but I am eternally greatful. It isn't often that your spouse offers to let you spend $1000 dollars for a piece of equipment when you already have somewhere in the vicinity of $2500 dollars tied up in a telescope. In addition to the 20 inch scope I now own a very good 12 inch Dob which serves both as a regular at the house but is my standby for carrying to star parties away from home. Remember back in 2000 I was trying to justify spending $650 dollars for that very first scope?
Not everyone will make the moves that I have made and continue to buy larger and larger scopes. You can purchase a very good 8 inch DOB from one of the catalog companies for about $350 dollars and a 10 inch DOB for around $550 dollars. Either of these scopes are very user friendly and are very functional.
Many folks will opt for a very inexpensive scope from a department store or some similar retail outlet to give to a young observer or someone just beginning in astronomy. The idea behind a purchase like this may be to determine if the person will become truly interested in astronomy or if it is just a passing fancy. I understand the thought behind this rational but it will almost always backfire. If the scope mount and the scope itself are made of cheap materials they will probably prove to be more of a hinderance than benefit to your potential astronomy observer. Most of these scopes are less than desirable in overall workmanship and are usually very hard to use. The tripod may be very lightweight and unable to hold the telescope without continual shaking. No matter how good the telescope may be, if the mount it is on is loose and wobbly you will never be able to see very much in the eyepiece. In a majority of scopes of this quality the focus mechanism will never allow you to get a object into good focus because the gearing is not very well machined. It's a lot like a small bolt in a large hole---it just flops around and is never very solid. There will be a lot of "department store" scopes for sale this Christmas season and many of them will be advertised as "computerized". These scopes will sell for something around $99/$350 dollars and are very tempting for the first time buyer. I would never advise you not to purchase one of these scopes. They may be exactly what you want and need. What I would advise you to do is this---visit with someone that owns a scope. Talk to them about the likes and dislikes of their scope. If possible, try using the scope to see how it works for you. Better yet, if possible, visit a astronomy club one night when they are observing. They will likely have several scopes representing all types and sizes. They may not all agree on the one best scope but at least you can get the pros and cons from more than one person. If you decide that observing is the thing you want to do or if someone in your family wants to get into observing, then go out and find yourself a telescope. If you are still undecided and want to investigate still more before you make a purchase, consider buying a good pair of binoculars. There is an untold number of objects than you can observe with binoculars alone. At least if you decide that star gazing isn't for you, the binoculars can be used for a lot of other activities.
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