Darin E. Fields' Astrophotography Pages

Thoughts on Building an Observatory

I constructed my observatory in the winter of 2000 and spring of 2001. As winter of 2004 approaches, I thought that I might reflect a bit upon how this structure has changed my engagement with the hobby. For those of you who are not interested in blog-like reflections, feel free to move right along to the construction details.


The answer seems simple: to enjoy the benefits of having your equipment setup and ready to go "all the time." But this also means that your equipment is, to varying degrees, permanently installed in an outdoor building that is subject to the same external weather conditions as any outdoor shed. So, very real considerations about having an observatory must extend beyond convenience to include sky quality, usability, durability, weather resistance, security, and, on a more philosophical level, one's desires in relation to the hobby. The short and sweet of it in my case is that although I live only about two and a half hours from some of the darkest skies in the eastern United States (Cherry Springs State Park in Pennsylvania), I have not been out in the field with my equipment since my observatory came online three and a half years ago. In fact, I have moved farther and farther from portability as I have systematically worked to remove variables like the need for rebalancing and positional adjustments in my equipment set-up.

What pushed me toward observatory construction was time and personal comfort. At the time that I dug the hole for the pier, I had placed the order for my Losmandy G11 and was already spending roughly an hour setting up my modest Orion Skyview equipment and ST-237 for observing and imaging. I knew that the G11 represented a significant increase in weight and complexity. My G11 arrived in December 2000 and I spent the winter months of 2001 setting up and tearing down my new equipment in temperatures that frequently dropped into the single digits. I routinely worked in ski pants, down jacket, and gloves. I heated my computer equipment, and myself, with heating pads. I would sit in my yard in freezing cold weather surrounded by extension cords and equipment watching image data come down. I knew then that I had made the right choice to build. I knew it was right not just for the time and comfort reasons (though they were significant), but also because I had concluded that a more stable installation would eliminate many variables in the imaging process.

I truly respect the imagers I have met at Cherry Springs and elsewhere who have careful routines for setup, polar, and drift alignment. But, honestly, it made me crazy. Astroimaging is all about variables--of sky conditions, equipment operation, data collection, and post-processing. An observatory allows you to offset several of these variables with a certain degree of consistency and stability. The many repetitious steps of astroimaging can yield very different results depending upon the variables. Success is built by nailing down the repetition and scaling back the number of variables with which you must contend. Maximizing the value of time spent drift aliging, and allowing you to leave your equipment "parked" between imaging (or observing) sessions, the observatory eliminates the need for ground up setup and tear down--increasing your time spent actually observing and imaging. As a result, nights do not need to be perfect to spend time observing or imaging. I can be "operational" in less than ten minutes, and I can close up just as fast. If the satellite image indicates that I may only get two hours of imaging, I will still seriously consider spending some time at it. In this way an observatory adds significant value to the hobby because I live in a area where clear, optimal conditions are relatively infrequent--at least by comparsion to where I grew up in Tucson Arizona!


For many people who are handy, building the observatory is not a big deal. I think that's great. A lot of people choose to modify garden sheds or simply purchase construction plans. Building my observatory was a significant project for me. I chose to build it from scratch, to make my own plans, and pretty much to figure it out all by myself. I wasn't really sure anything would work until it was done. Of course, I relied heavily upon what others had done before me. Bill Arnett's outstanding list of amateur observatories is an indispensable source. Some of the observatories listed there are truly works of art as much as functional buildings. Check out, for example, Bill Arnett's observatory, Ptolemy's Cafe.

In preparation for building my observatory, I spent a good bit of time at the local Home Depot and Lowes nosing around in the garden sheds, carefully examining the framing, roof structures, siding materials, flooring. I found sheds about the size I intended to build and actually inventoried the supplies involved in order to estimate the cost. Interestingly, pre-built sheds are a pretty good buy overall. Still, I wanted to do-it-myself. I bought a "How-to" book on building garden sheds and small outdoor buildings. I relied mostly on the internet sources for ideas on how to configure the roll-off. About the only other thing that I did that made the construction different from a shed was the use of strengthening elements such as steel hurricane ties on the walls. I did this because the building needed to have square structural stability without the roof in order for the roof to operate properly. More or less the rest of what I did is adequately described in the ensuing pages. Total cost of the project, including the concrete pouring, and the cost of the pier was around $1500.

Life with the 'Zerb

Having an observatory has transformed this hobby for me. It has deepened my passion for every aspect of the hobby while at the same time reducing its concomittant frustrations. Additionally, I like to think that the quality of my imaging has improved significantly. I know for a fact that the volume of my imaging has increased many-fold. As I note in "Updates," I have made a few modifications and improvements since initial construction. The warm-room is a real pleasure when it is colder--though I stay inside the house when it is extremely cold. That ability has been enabled by the CAT5 cabling and remote operation, which allows me to be in the house with the family while imaging. It is not perfect, not totally remote (I still occasionally have to rush outside if a cable snags or some such thing), but overall astroimaging is very much integrated into my regular evening existence. My kids join me occasionally at the computer as data comes in. My wife's computer is in the same office, and she will often do her work while I'm imaging. I do occasionally hide out in the observatory, but I no longer have to be a recluse to enjoy my hobby. There have been, however, a few other unexpected surprises.

When you store your lawnmower or leaf blower outside in a shed you don't worry about spiders, ants, perhaps wasps, birds, mice, even rabbits, but put your precious Takahashi scope and SBIG camera outdoors and you take up another hobby--pest exterminator! Preventing against pest infestation is a continuous activity. Wasps are particularly fond of of building nests in the eaves and crawling inside the observatory. One year birds pushed out the insulation under the Ondura roofing and kept building nests in the roll-off channels. Very annoying. Spiders string webs around the scope and seem to have a liking for power supplies. Last year I fought an ant infestation that trailed its way up one side of the observatory and down the other. While furry critters can't get inside the facility, they do enjoy being underneath it.

Fortunately, my construction job has proven to be quite weather resistant. The roof has held up wonderfully and the facility has no leaks--except a small one that recently developed near the rear door and required some caulking. But the observatory has been through the remnants of several hurricanes that have moved up the eastern seaboard, including Isabel in 2003 and Ivan in 2004 with no problems whatsoever. It has withstood three winters and several big snowstorms. When it snows I use a long pole with a flat board on the end to pull snow off the roof before rolling it off. One year the snow was piled so high on the north side of the observatory that is extended nearly five feet up the side of the structure in a big pile. Winter skies in Northeastern PA are among the few times that clear dry conditions can prevail for several days. Being able to take full advantage of that time is a great pleasure.