Manual Barn Door Tracker

A barn door tracker is a camera attachment camera mount used to capture long exposures of night sky images.
Manual barn door tracker. 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. If you re in the northern hemisphere this is as simple as pointing your tracker s hinge at the north star. With a barn door tracker it s the same concept except you align the trackers rotation with the rotational axis. There are many types of barn door tracker.
Note also the red dot sight for alignment. There is a motorized version of this mount. To drive your tracker you will be rotating a threaded rod. The design is known from the 80 s as a barn door star tracker or a scotch mount.
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 double arm design was first described in an article by dave trott published in the february 1988 issue of sky telescope magazine. Shoot stars planets and other nebulae with a camera that is. 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.
Acquired data with least squares linear fit. This guide is for a manual single arm version which consists of a single arm board and is operated manually by the user. Tracking was accomplished by continuously turning a long inch screw at a rate of one revolution per minute while the exposure was in progress. So i measured a nice and constant 7 255e 5 radians second over 10 minutes.
Then i let it run with my tracker for a while and did some least squares fitting to see how it was working. Calibrating the barn door tracker with a digital level. The modest success of the manual version encouraged me to motorize it. The mount shown here employs a type 4 double arm design.