Barn Door Tracker

grabcad

This device was crafted at home using basic hardware from stores, a red dot sight, and a DIY 3D printed part called a "Barn Door Tracker" made on a desktop printer. It's used in photography for taking long exposure shots of celestial objects like the moon or comets, eliminating the blurring effect caused by Earth's rotation. This technique was seen in famous shots of Halley's Comet from the late 90's, where a clear and detailed photo was taken with an incredibly bright blue and white tail, while background stars remained sharp and not blurry. When attempting to capture similar photos without such a device, the results usually show blurry backgrounds. To achieve sharper and more stable long-term exposure photos of night sky objects, a small stepper motor and special gears are connected to the tracker in a way that makes its hinge plates expand at a rate matching Earth's spin as closely as possible.