Manual Barn Door Tracker

Note also the red dot sight for alignment.

Manual barn door tracker.

Calibrating the barn door tracker with a digital level. There are many types of barn door tracker. Acquired data with least squares linear fit. The double arm design was first described in an article by dave trott published in the february 1988 issue of sky telescope magazine.

So i measured a nice and constant 7 255e 5 radians second over 10 minutes. More information on other types of barn door tracker can be found at starnamers blog and a motorised version is detailed on this aticle on petapixel. If you re in the northern hemisphere this is as simple as pointing your tracker s hinge at the north star. A barn door is a specialized type of equatorial mount.

There is a motorized version of this mount. Tracking was accomplished by continuously turning a long inch screw at a rate of one revolution per minute while the exposure was in progress. It is a simple but effective way of eliminating the star trail effect of night sky photography without expensive equipment. To drive your tracker you will be rotating a threaded rod.

No arduino no stepper motors no gears just a simple motor turning a threaded rod this barn door tracker rotates your camera at the exact same rate as the rotation of our planet a requirement for taking long exposure photos. With a barn door tracker it s the same concept except you align the trackers rotation with the rotational axis. Shoot stars planets and other nebulae with a camera that is. Then i let it run with my tracker for a while and did some least squares fitting to see how it was working.

The design is known from the 80 s as a barn door star tracker or a scotch mount. The modest success of the manual version encouraged me to motorize it. There is a lot of information in the internet where you may find sophisticated designs that try to minimize the systematic errors of the first design. The mount shown here employs a type 4 double arm design.