Like with the eye, the telescope itself must be properly prepared for use before observing begins. The most important thing that you need to do for your scope when it is set up is to ensure that it has time to become thermally stable before you begin to do any serious observations. If the air in the telescope is warmer than the outside air, it will distort the image to the point you may not be able to focus on anything. A closed-tube telescope like a catadioptric or a refractor may need as much as thirty minutes to cool down. An open-tube reflector will cool down much more rapidly.
The observing site itself must also be chosen with care. When selecting a place to observe, you must consider three criteria. First is the presence of extraneous light. Light pollution can quickly turn an observing session into an exercise in complete frustration. Even in the most light polluted areas, you can find a place to observe that has somewhat dark skies. Large parks make excellent observing sites because they can put a few miles between you and the "light domes" that envelop large and medium-sized cities. Secondly the site must have reasonably clear horizons so you can see down to the haze levels. If trees stick up too high in close to you, you will not be able to see much more than straight up. Most large parks have an open meadow where observers can set up not far from their cars. The third important thing is to avoid large expanses of asphalt. Dark pavement will radiate heat for many hours after the Sun goes below the horizon, creating turbulence in the air adjacent to the ground and creating unstable conditions and bad seeing. It is a good idea to scout out the site in daytime. Get familiar with the horizons and exactly where you will be setting up. Know which way north is and how you will align on it.
The telescope itself is not all you have to check on. You will also have a box full of cameras, eyepieces and filters. The most important thing you can do is make sure that it is all organized! You are going to have to be able to find absolutely everything in the dark, without the use of anything brighter than your red map light. All your eyepieces should be stored in order from longest focal length to shortest. Barlows should be stored together near the eyepieces. Filters should also be all together and stored in spectral order with blue or violet at one end and red and orange at the other end. The other side of your box should be dedicated to your cameras. Lenses are stored in order of focal length and other accessories should be close by such as cable releases. If you find yourself fumbling for equipment in the dark, you may as well not have it if you can't find it. Even worse, not being able to find equipment is an invitation to lose it.
A seemingly silly thing to do, but an exercise that can be very helpful is to bring all your things into a dark room and practice assembling it in the dark. This is a common military exercise that all military infantrymen must perform during basic training, learning to disassemble and reassemble their rifles in total darkness. Try it for yourself and practice setting up your equipment, go through some common changeouts of eyepieces and other equipment just the way you'll do it in the field. Go through it first though in full light. This will give you the chance to see how everything fits together, what is tight, what is loose and what is j ust right. You would think that precision-made equipment that is industry standard should all fit together but sometimes you can get surprised. The eyepieces for my 4.25-inch Bushnell do not fit my 8-inch Celestron in quite the same way, they are slightly loose. In reverse, the eyepieces of the Celestron have barrels that are a bit too long to fit the eyepiece holder of the Bushnell. The Bushnell eyepieces were not threaded to accept filters.
Cameras can also give you a surprise especially if they were used equipment. I bought a Minolta 35-mm camera for use with my Celestron and found that it did not work in quite the same way that my old one had. The attach point for the cable release was on the lens mount instead of being on the shutter button as it was on my old Yashica. I also found that the threads for the tripod receptacle were not deep enough to allow the bolt on the Celestron piggyback mount to fully tighten against the mount causing the camera to be very loose on the mount. I had to devise a spacer for the bottom of the camera to ensure it would not rotate on its bolt while I was taking pictures with it. When that did not work, I resorted to Velcro. So check out everything in daylight including how you plan to attach each accessory in all the various different ways. Once you are certain that everything fits right, then try everything out in the dark. When you are comfortable with how everything fits and your organizational plan, then its time to go out into the night and put it all to work.
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