In a perfect world, you reside in an area with a perfectly dark sky and there are no trees to obscure the view. Humidity is always low, insect life is non-existent and the temperature rarely strays from the low 70s.
Unfortunately, not many of us get to live in San Diego. For me, living in the mid-Atlantic area, winters are cold and windy while summers are oppressively hot and filled with many swarms of various sized flying bugs. Weather patterns are frequently stormy and when weather systems stall (as always seems to occur whenever an eclipse or other monumental event occurs) the sky stays cloudy for as long as seven to ten consecutive nights. Worse than that, the prospect of finding a dark sky area is daunting at best. Between Boston and Washington D.C., the skies are almost hopelessly floodlit in most areas as lights from major cities like New York, Baltimore and Philadelphia and lesser cities such as Wilmington, Atlantic City and Trenton fill in the gaps. This does not mean that finding a dark sky site is impossible and in fact if you intend to pursue this hobby with any degree of seriousness, then this needs to be your first endeavor.
This is where finding a good astronomy club can be vital. Remember that not only must the site you select be dark but it must also be safe. After joining a local astronomy club when I moved to Delaware, I learned that they had access to a dark sky site at Tuckahoe State Park, not far across the border in Maryland. I could also set up shop about fifty feet from my house where trees would not interfere though streetlights make deep sky viewing very difficult. The dark sky site is on a baseball field in the center of the park and is dark enough to draw large crowds annually to the club's two large annual star parties. Thus I have sites and opportunities for doing both casual stargazing and also for doing deep sky work under as close to ideal conditions as one can find on the east coast. The next challenge then becomes getting all that equipment to the site. Here it becomes vitally important to ensure that all your equipment is stored in an organized way.
As I elaborated on in Chapter 2, if I am going out to do serious photography, I can get all my stuff out to the car in only three trips. The telescope comes first in its storage case. The tripod comes second, then the eyepiece case and personal backpack and laptop on the third trip. It all fits comfortably in the back of my Mercury Mountaineer with some room to spare after the back seat is folded out of the way. All the optical components ride in foam lined cases to protect them from the bumps and jiggles of the road. The laptop is protected by the padded case that it normally travels in. With all my stuff loaded, its time to head out.
Leaving about an hour and fifteen minutes before sunset (6:30 PM) gives me time to get to a local convenience store to pick up my midnight snacks. A cold roast beef sandwich and a bottle of water and/or fruit juice will set me up for the night. If I need some munchies, I'll grab a bag of potato chips for something extra. Then it's on to the park. Arriving there about at sunset, I will pull my car onto the observing site and open the back. Pulling out the tripod, the first great challenge will be to find a spot that is as close to perfectly level as possible. Once level and with the tripod oriented roughly north, I will then go about getting the wedge installed and polar aligned. Since the pole star will not yet be visible, I will use a lensatic compass to set up the initial north alignment of the tripod and wedge. The trick to using a compass is to take great care to account for magnetic variation. Variation is the error that occurs in compass indications as a result of the difference in location between true north (Earth's rotational pole) and magnetic north. The magnetic north pole is actually located in extreme northwestern Canada. At Tuckahoe State Park, the value of magnetic variation is about 11 degrees west. From my position, the needle of the compass points about eleven degrees west of where true north actually is. The telescope therefore must be set up not on the indication of magnetic north, but eleven degrees to the east of magnetic north. Working with care, it is possible to point the telescope within a few arc minutes of exactly due north. The telescope is now roughly aligned along the east-west axis, now it must be aligned north and south. The equatorial wedge is adjusted by means of a knob that drives a jackscrew, raising or lowering the tilt plate of the wedge. A scale indicates latitude on the side of the wedge. Once this is set, I am now within a fraction of a degree on both the north-south and east-west axis for alignment.
Mounting the telescope is next. The Celestron Super C8 Plus has one particular design flaw that is somewhat annoying. The two declination circles are adjustable, which they should never be. They occasionally need to be reset to ensure that when the telescope is pointed straight up with respect to its base that the circles read 90 degrees. To do this, I will place the telescope on a flat surface and check that it is level with a bubble level. Then I will raise the scope to a vertical position and use the level to check that it is straight and vertical. The setting circles can then be adjusted to 90 degrees. This is a pain in the proverbial neck that should not be necessary, but occasionally must be done. With this small maintenance task out of the way, the telescope is then ready to be mounted on the tripod. Three heavy-duty bolts secure the twenty-three pound telescope, fork arm and drive base assembly to the wedge tilt plate. The first bolt is threaded on the drive base then fits into a slot on the top of the tilt plate. After tightening the bolt, the other two bolts then can be screwed in. I must of course take great care to avoid moving the carefully aligned tripod during this process.
Finder scope alignment is another task that is best accomplished under daylight conditions. I will carefully point the telescope at the pointed top of a stationary object like a house or structure and carefully center that target in the main scope. Do not use a treetop or something else that sways in the wind. Make sure that the target you select is at least 200 yards distant. At this minimum distance, the focus of the finder and the telescope on your target is about the same as it is on the stars. Finder alignment is much easier to do during the day when I can follow the lines of the alignment target to find the point at the top of that house. I will then switch to a high-power eyepiece and center it again in the main scope. When that is done, I will then carefully use the three setting screws in the finder scope bracket to carefully center the target on the finder crosshairs. Proper finder alignment on my scope is super-critical because not only do I need it to find objects in the sky but to accomplish the precision polar alignment since on the Celestron the finder also serves as the polar alignment telescope as well. Once aligned, I will install the batteries in the reticule illuminator LED and place the LED and battery pack in its receptacle on the finder scope. Normally I keep the batteries out of the illuminator since they tend to die quickly if the LED is inadvertently left on, something that a weak design and a weaker memory makes very easy to do.
The next job is to set up the power supply battery. This is a simple 12-volt DC automobile battery. Batteries of this type are great for astronomy because they supply a huge amount of amperage. The batteries are intended for use by high electrical draw items like car starters so there is plenty of power available for a 400-watt AC inverter. Because the astronomy equipment is relatively low amperage, the battery can sustain my equipment through a night of work on a single charge. I set the battery on the ground near the telescope and clip the inverter to the terminals. This will allow me to power the computer from the battery and the computer then can distribute power to my CCD. I will then set up a portable table (which normally is always left in the car) to set up the computer. The computer is plugged into the inverter and then started. By now, it is about forty-five minutes after sunset and it is time to begin observing.
The last critical task to be performed is the precision polar alignment. As soon as Polaris begins to come into view, I will rotate the telescope to 90 degrees declination and sight through the finder scope. In addition to a crosshair sight, the scope also has a dual ring to allow for precision positioning of Polaris. A template provided with the telescope shows exactly where Polaris should appear on the ring. With the telescope already aligned within a degree of the correct position, only some minor repositioning of the mount is required to gain a precise alignment. With this accomplished, it is not necessary to guide the scope during longexposure photography on the declination axis. The only corrections that will be required will be in right ascension to account for the occasional variations in the accuracy of the telescope's gears. My scope uses a Byers designed worm gear that for the time was the most accurate clock drive ever produced for a telescope. Even by the standards of today's GPS computer driven telescopes, it is still pretty good. With precise polar alignment, I can take photographs of up to several minutes without any guiding at all.
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