Double Arm Barn Door Tracker

The hinge is aligned with a celestial pole and the boards are then driven apart or together at a constant rate usually by turning a.

Double arm barn door tracker.

Original concept by dave trott. Sky telescope april 1989 p436 p441 very good. How to build a double arm barn door tracker jefferson lab home page science education home page construction notes photos page sources. Double arm barn door tracker.

Make sure everything is square and moves freely clap the 2 hinged boards together and shout action a few times like they do when making movies if it makes a nice clack sound it should work well for a star tracker now measure 228 55mm from the center of the hinge pin down the middle of the board and mark the drive rod holes do this on. A double arm mount offers much greater accuracy than conventional designs. A simple single arm barn door tracker can be made by attaching two pieces of wood together with a hinge. Smits notes that all of dave trott s drives including the single arm version have the drive screw mounted as the expanding base of an isosceles triangle.

An inexpensive route to astrophotography has long been the scotch mount also known as the barn door drive after its appearance or the haig mount after its inventor. To use it the tracker is set up in the field so that the hinges are aligned with the earth s axis of rotation. Construction plans for a star tracker. Sky telescope february 1988 p213 p214.

His paper a mathematical analysis of the double arm barn door drive appears on pages 155 160 of the december 1988 monthly notices of the astronomical society of south africa. For some of my longer exposures i use this device which can track the motion of the stars across the sky while the image is being made. The 6x30 mm finder scope is parallel to the hinges so it can be. First cut the 500mm length in half and mount the hinge.