By Chris Fellows, Serenity Mobile Observatory
Your first telescope – Untangling the Gordian knot of choices
You’ve made the decision – you’re going to buy your first telescope, but which one? There are dozens of choices at a huge span of price and capabilities. How do you choose? In this article, I hope to tame the decision beast that stalks this important choice. I will provide links to example equipment of the type I am discussing and systems that I have used or have some familiarity with.
I want to make it clear: I have no association with any telescope manufacturer and these are simply my opinions based on my experience. I am also going to assume a novice level of expertise for this “Your first telescope” article. I also will not be recommending any department store equipment – I am going to make the assumption that if you are interested enough to read an article like this, you are also willing to invest at least a few hundred dollars.
There are three main components of any telescope setup: the optical tube assembly (OTA), the mount, and the tripod or pier. In this article I am going to concentrate on the OTA but I don’t want to give the impression that the OTA is the most important or most expensive part of the setup. Depending on your use case, the mount can be more important than the OTA. We will talk about the mounts and tripods in a future installment.
Telescope OTA types
There are three basic designs for visible light telescope with several sub-varieties under each of those categories. The cost of the various types also varies widely based mostly on the complexity of the optical design.
Table 1 – The dollar signs represent a range of prices as follows $ = $200 to $500, $$ = $500 to $1000, and $$$ = over $1000 (this is a very wide range category)
All three designs have sub-designs that were developed to address specific problems with the basic setup. For example, refractors come in both Achromatic and Apochromatic designs – the latter avoids most of the chromatic and spherical aberration effects of the prior. It would take volumes to go over each sub-design and the reasons they were developed, so I recommend that once you decide on a basic design you do some additional research to finalize your decision. Each basic design has its own pros and cons other than price and portability. The following table describes some of those.
Here are some examples of each basic design you can buy online. I have picked one low cost and one higher cost example from each type. Remember, these are only the OTA (optical tube assembly) parts of a complete telescope package. To these you will have to add a mount, a tripod, and accessories such as eyepieces and other do-dads.
- Maksutov Cassegrain
There are many, many more choices than the ones I have outlined here and many, many more places to buy than OPT (a telescope retailer), where I grabbed these prices from. I picked OPT because I buy all my astro-stuff from them and I know they are knowledgeable and helpful to their customers. I am sure you can find many of these on Amazon as well.
OK, this is getting to be too much information for a single article so I think I will stop it here for now. I am sure there are many questions so please feel free to hit me up in the comments or on my website below. I will move onto mounts in next week’s article (It is a little easier to wrap your head around). Until then, keep looking up!
Chris Fellows, Serenity Mobile Observatory
Find Chris on Facebook (or, if you’re lucky, at your campground). (Editor: Check out his amazing photos on his Facebook page!)
Editor: Here’s a link to telescopes at Amazon.com.