Cheap Man's Observatory

While I live in a rural part of our county, and the skies are startling crisp at the Zenith, I am located near an intersection that features a safety light, store light, and neighbors on each side of my property. Up to this point, much of the glare from these sources has been avoided by setting the telescope up in the shadow of my storage building. But light is still slipping into some of my photos as a gradient and if I take one step the wrong direction I lose my dark adaptation. Since a permanent Observatory housing for my telescope is not feasible at the moment, I wanted to try a low cost solution to block out a lot of the stray light.

My plan is this: find something to act as 10 foot poles that would extend from each corner of my building. Between my building and these poles, I will hang tarpoleun to act as a temporary wall. This will hopefully block out extraneous light while having the advantage of being quick to assemble and disassemble as necessary.

Project Materials:

3 8x10 tarps (I could only find 10 mil thickness, colored gray on one side and Brown on another)

2 PVC 10 foot long pipes

2 cinder blocks

1 roll of duct tape

1 box of eye hooks

Project Materials Needed Later:

1 roll of twine

2 cans of matte black spray paint

4 camping tent stakes

First, I measured up the PVC 8 feet and screwed in two eye hooks at a 90 degree angle from each other. Next, on each corner of my building, I measured up the same height and screwed in an eye hook on each side. Now I can use the reinforced eye holes in each tarp to hang my temporary walls.

Now I only needed to secure the poles and I should be set. To do this, I liberally applied duct tape to the base of each pole and a cinder block. In hindsight, not the best idea I never had.

The PVC turned out to be too weak to really hold each tarp, so I had to break out the twine and tent stakes to string up some guide wires opposite the directions of tension created by each tarp.

This created my enclosure and after each session I could unhook the tarps and be done with it. Now to test it!

Once settled in after sundown, I noticed a significant reduction in glare. Two problems were obvious though. First, the caution light at the intersection was just high enough to slip over the edge and create some glare on the top foot off the glossy tarp. To fix this, I took some matte black spray paint and coated areas that were affected. Problem solved (mostly anyway). Second, because the tarp was not as thick as I would like, my neighbors safety light created a soft glow of against one side. Another application of spray paint should fix that!

In the end, I achieve the desired effect of greatly reducing the effect of my neighbors' lights. Is it the best solution? Definitely not. Is it much cheaper than a dedicated Observatory? Absolutely. Will my dog rip it down when my back is turned? Almost certainly.