Bruce Johnston's
Roll-Off-Roof Observatory

Located southwest of Flint, Michigan, in Gaines Township.

The primary goals when designing this observatory were to first, make it comfortable for one person, for viewing and for CCD imaging.  The second goal was to be sure that no part of the walls would have any significant flexure without needing any additional supports. I am putting in shelves, etc. but I wished to put them where I want them; not where I need them!!  The result is shown.

The size of the observatory I decided on was 8 feet X 10 feet .... enough room for several people to occupy at one time... with a concrete pier being offset from the center of the building.  The center of the pier is located six feet from the North wall and four feet from the Southern wall.  Since most of my observing and camera manipulation would be done from the North side, this left me with plenty of room.

As usual, the roof rolls off to the North of the building, with the door on the South end.  The door is split into two sections so as to allow the roof to easily clear my 10" LX200 when rolled back.

The roof/wall ended up to be quite heavy, but because it rolls so smoothly, even my wife can roll it back!  Not shown, is a handle that is attached to the inside of the upper wall,. that I use for pulling the upper section back. It was made from 3/4" water pipe and looks very similar to a towel rack.  To the surprise of many, I can roll the roof back with only one hand!  Because the upper section is so sturdy, the wall doesn't flex at all when I pull on the handle and roll the roof back.

Construction of the Pier

Construction of the lower section

Construction of the upper section

Conclusion: After construction reached the stage shown in these images, two power lines and a "just-in-case" set of three telephone lines from my house, have been run underground to the observatory (the trench is visible in several images), five outlets have been installed, shelves for my eyepiece box and my CCD cameras have been made, and two lights with their on/off switches have been installed... red and white lights, naturally.

I've trimmed and painted the building, covered the power line trench, installed a small table for sitting my computer on for CCD imaging, and various other minor improvements. It works nicely as it now stands, and it has made being an "astro-nut" fun !!

(But I still miss my tree-stump pier!! That thing was the sturdiest, most vibration-free pier that I have ever seen!!).

First light with a 'scope ..... August 1, 1998!

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Enjoy Astronomy!!