Yesterday I bought my first telescope: the SkyWatcher FlexTube 25 cm Dobson with a flexible tube.
This was not an impulse purchase. Over the last couple of months I’ve been wondering, is this something I want to keep spending time and money on? And why? To test if the topic would keep being interesting, I enrolled in two coursera courses: Galaxies and Cosmology by George Djorgovski of Caltech, and Analyzing the Universe by Terry Matilsky of Rutgers. In the meantime I also listened to the Astronomy 162 podcast of Richard Pogge when commuting. If anything, these to courses only enlarged my enthousiasm!
While the courses explained history and latest ongoing research, they didn’t cover amateur telescopes. There are a couple of youtube video’s that help newcomers choosing their first scope, and lots of material online about the different kind of telescopes. So many choices! In the end I had to make a choice, and my reasoning to buy a Dobsonian was the following:
- The Dobsonian mount is much smaller than an equatorial mount with tripod, this scope has a modest presence in our garage.
- One guy at the local observatory was very happy with his Dobsonian. It was a bit small though, so you’d need a table to put it on.
A Dobsonian mount is somewhat preventive of astrophotography, but I reasoned I did not want to do this from my backyard anyway:
- I do not want to spend the money of a decent car on the scope.
- I do not want to spend countless hours on acquiring images and post-processing, with mediocre equipment.
- For deep-sky photography, itelescope.net provide per-minute access to professional telescopes, on a pay per usage model
- The telescopes from itelescope have as additional advantage that they are not located in my ligh polluted backyard, but at three different places on both the north and southern hemisphere.
Would I need a scope at all? After all, the nearby observatory is open each fortnight. I’ve seen many starry nights go by when it was not a scheduled stargazing session. So yes, a local telescope for the easy grab is definitely a plus!
Goto seemed quite handy, but after mailing with the local telescope shop, where I also mentioned spending perhaps 30 minutes on a sky watching session, I was advised to not buy a Goto system, since that requires at least 15 minutes setup time per session. This seemed reasonable.
My final choice was telescope focused on one thing: backyard observations with the eye. Therefore I favored buying a larger scope, rather than electronics and heavy equatorial mount for tracking and goto. I bought a 250mm diameter tube, with simple dobsonian mount, together with a good eyepiece: The SkyWatcher 10″ FlexTube on a Dobsonian mount, with TeleView 82 degrees 12mm eyepiece.
Unpacking and assembly of the scope took about an hour, and is a bit like assembling an IKEA cabinet, no surprizes there.
The OTA is not balanced. I had to tighten the holds a lot to prevent it from moving down. A drawback of this tightening is that vertical fine movement of the scope is hampered.
Later that evening the first stars became visible. Lookup the brighter of the three in the finder scope, then on to the main tube. It was Saturnus, clearly marked by its rings!
Even further in the evening, looked at Mizar, a double star. Nice. I also tried to find a star cluster in Cygnus, but that proved difficult. A goto system would be nice!
- Scope assembly is solid and sturdy.
- OTA is in disbalance.
- It is hard to find objects when you don’t know what to expect to see.