Barn Door Tracker

This is a device that was made at home using some basic store bought hardware, a red dot sight and a diy 3D printed part ( printed on a desktop 3D printer ) called a " Barn Door Tracker " and it is used in photography where a long exposure photo of a celestial object ( such as the moon or a comet etc. ) is to be taken and it will eliminate the blurring effect seen in the background thats caused by the rotation of the earth. This seen in famous shots of Haley's Comet in the late 90's where an incredibly clear and detailed photo was taken of the comet and its amazingly bright blue and white tail were shown and the background stars remained clear and weren't blurry. ( Which usually is the case when attempting to achieve the same type photo without such a device ) A small stepper motor and some special gears would be connected to it in a way where the hinge plates of the tracker will expand at a rate that's as close as possible to the rate that the earth spins. Allowing for much sharper and more stable, long-term exposure photos to be taken of objects in the night sky.