It is said that the best telescope to have is one that is used and the worst to have is an unused scope. These few words hold a lot of truth. After being into astronomy for a while, the "new" begins to wear off and the ole body begins to listen to that inner voice that says, "I'm too tired from work to set up the scope tonight". What the voice really means is that you would love to spend a few peaceful minutes at the scope but the hassle of set up and polar aligning takes so long that by the time you would have the scope ready, do the observing, and taking down the scope, it would be well past your bedtime. And after all, you have to get up early tomorrow for another days work.
This is why I decided that it was time to build my own backyard observatory. Ideally, an observatory should be built at the darkest site available but in my case, that would involve driving several miles to get to such a place. Additionally, my back yard, while maybe not the darkest place around, IS close to my bedroom. I needed something that would allow me to be up and running with the scope in just a few minutes and also to allow me to close up shop in just as short a time.
I finally decided a dome type observatory was out since I have read terrible things about the effects that warm air drafting has on views through the slit. A roll-off roof obviously was the thing to have, and with a farmer's general knowledge of carpentry and construction in general, I decided to build my own. The exterior walls are covered in vinyl siding as are all exposed wood surfaces.
The 8 inch LX 200 rests on a 6 inch steel schedule 40 pipe that is buried 4 feet in the ground with 15 sacks of concrete around it. It is VERY solid. Photo on the right shows the 90mm Meade ETX mounted piggyback with Losmandy rings and adapter plate.
Well, the verdict is in about using a moveable focus mirror guidescope and a moveable focus mirror SCT to image with. The answer is FORGET IT! Exposures of more than about 10 minutes will invaribly show the results of mirror movement in either one or the other scope. SCTs must be guided with off-axis guiders to get around the mirror "flop" problem.
View showing interior lighting controls. The red light is wired into a variable dimmer control to preserve night vision. The ST-4 autoguider control box is shown on the table. I have since built an angled rack on the wall to hold the control box to ensure that it can't accidently be knocked off to the floor. The imaging head of the ST-4 is on the scope.
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