Getting Started
I want a Telescope
Time for a new Telescope
Eyepieces and Filters
Book Reviews
Free Astronomy Software
Our First Night Out
Orion SpaceProbe 130ST First Light
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God, Genesis and the big bang
Time To Reflect
It has been a while since I first wrote, “I want a telescope”. In that
article I discussed how we decided our first scope would be an 8” dobsonian.
As I contemplate buying a new scope, I thought it would be good to ‘reflect’
(bad pun intended) on what I have learned.I must admit we made an awesome decision when we bought the dob.
We have on multiple occasions viewed the Moon at 600x. Wow! It’s like flying over it in a jet. 600x is far greater than the theoretical maximum magnification of 400x for this size scope and absolutely blows away the typical useful magnification of 200 – 250x. Of course it was the Moon and the Moon is very bright.
Deep space objects like the Ring Nebula, and the Hercules cluster we have often viewed at 266x, which also exceeds our expectations. We have seen the red spot on Jupiter and shadows on the planet from the moons encircling it. Saturn, while small in the eyepiece, remains a phenomenal sight. We have seen a great amount of detail in the Whirlpool galaxy.
We have had many compliments from others including fellow scope owners on the bright images seen through the scope. As an all around general-purpose telescope this thing has been an excellent investment. So why am I contemplating a new one?
Putting It All In Focus
I mentioned in an earlier article that I regularly use my Oberwerk binoculars more than I do the telescope. The Oberwerk 11x56’s, by the way, are still an awesome viewing tool. The reason I use them more is because it takes lots of planning and muscle to drag a heavy scope out in the yard. It is even more work when you have given up viewing in your own yard because of trees and neighbors insecurity lights. Loading and unloading twice in one night is a lot of work. Binoculars take minimal advance planning. It would be great to have the light gathering ability and magnification of a scope combined with the ease of binoculars. The time has come for something lighter and easier to manage.
Another issue for us has been that star maps are plotted based on R.A. and Dec., which doesn’t translate easily to the Alt/Az of a dob. While an equatorial mount is going to require time to overcome the learning curve, I think it will reap major benefits in the long run once we learn it. I remain convinced it was a good move not to start with this type mount.
Tracking with a dob becomes fairly second nature very quickly. Still it seems it would be a benefit to have the scope do more of the work. This would free the observer to concentrate more on the object in the eyepiece and less on the equipment. The promise of easier tracking is the highlight of getting an eq mount to me. In fact tracking can be motorized. How cool is that?
So what do you have to give up to get all this? Well the big sacrifice for us will be aperture. We have been spoiled with our light bucket. In order to gain mobility and portability we will have to sacrifice size. In astronomy you will often hear aperture rules. All things being equal that is correct but all things are not equal. If a scope sits in the basement because it requires too much work to use it then it doesn’t matter if it is 8” or (drool) 30”. If it isn’t getting used regularly but the interest in the hobby is still there then something needs to be done.
There will be times when the big dob is worth the effort. We love to take it to star parties and show off the universe. There are nights on our own when long hours in the dark beg for the big scope. But there will be more nights when that isn’t the case.
Narrowing The Field Of View
I quickly ruled out a smaller dobsonian. They sit very low to the ground and lack the tracking ability I desire. I also quickly ruled out a refractor or a small mak. While both of these are excellent type scopes, I think they are better suited to planet observing than DSO’s. Also both are more expensive per inch than a Newtonian reflector. I need not only the weight to be light but the impact on the wallet to be so as well.
I then considered a 6” Newtonian scope. It was everything I wanted except it was a little more expensive than I wanted to spend and a little heavier than I wanted to carry. They seemed to run between 35 and 45 pounds. Next looked at 4” scopes. The weight and price were great but the lack of aperture concerned me. I had been spoiled by my first scope and wasn’t sure I could make that big of an adjustment.
As I continued my search I ran across the Orion Spaceprobe 130. It has a 5.1” (130mm) mirror and is available in two options – a regular tube and a short tube (130ST). The weight was in the mid 20 pound range and the price very nice with the short tube being a bit higher. The regular tube is a 850mm focal length scope. The ST is 650mm. At f/5 the short tube is a better option for astrophotography which I might try someday. The short tube is also a parabolic mirror which is found in better scopes which explains the higher price.
The 130ST sounded good to me but I had a few questions. It would have a wider field of view than I was used to, somewhere between my dob and my binoculars. That sounded like a good thing but I wasn’t sure. The main concern I had was the maximum magnification of this scope was significantly less than I was used to at around 250x. I needed advice.
Target Located, Time To Enjoy The View
I went to a meeting of our local astronomy club with specifications in hand. I like these guys. They aren’t snobs. They’re just everyday guys. Some of them might own a Nagler eyepiece but most say they aren’t going to spend that kind of money on a piece of glass. Most of them have 10-11” scopes but will tell you they use their 4” scopes more – for the same reason I am looking for a new scope.
They started throwing out ideas. As they narrowed their thoughts to fit my restrictions of cost and weight, they quickly decided that the Orion Spaceprobe was a good fit with my viewing style. Unanimously they agreed the short tube with its wide field of view would be excellent for deep space observing.
What about the lack of high magnification, I asked? They looked at me like my mirrors weren’t fully collimated, if you know what I mean. They all told me they seldom use higher magnifications anyway, not for DSO’s. I thought about it and realized the majority of our viewing is done between 48 and 200x which is doable with the 130ST.
So my new scope is an Orion Spaceprobe 130ST EQ. I ordered from High Point Scientific after asking them a few questions. Their pre-order support was phenomenal. I have emailed many companies with questions. Often I get no response. Occasionally I get comments that indicate no one was paying attention to what I asked as they never get around to answering the questions. In this instance I got a response within 24 hours. The salesman actually admitted he didn’t know the answer but promised to get back to me. Literally an hour later I got a second response with the answer clearly written out. That impressed me enough to include High Point Scientific in this article.
I hope you found something of interest here. If you did drop me a note.
Clear skies!
Copyright © 2007 by Kevin Sluder
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