Tracking was accomplished by continuously turning a long inch screw at a rate of one revolution per minute while the exposure was in progress.
Manual barn door tracker.
A barn door tracker is a camera attachment camera mount used to capture long exposures of night sky images.
The mount shown here employs a type 4 double arm design.
Note also the red dot sight for alignment.
It is a simple but effective way of eliminating the star trail effect of night sky photography without expensive equipment.
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.
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.
A barn door is a specialized type of equatorial mount.
If you re in the northern hemisphere this is as simple as pointing your tracker s hinge at the north star.
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.
The modest success of the manual version encouraged me to motorize it.
There is a motorized version of this mount.
Calibrating the barn door tracker with a digital level.
The double arm design was first described in an article by dave trott published in the february 1988 issue of sky telescope magazine.
There are many types of barn door tracker.
With a barn door tracker it s the same concept except you align the trackers rotation with the rotational axis.
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.
A followup appeared in.
Acquired data with least squares linear fit.