01-20-2023, 06:05 AM
Sun path diagrams. There are several different systems of projecting the imaginary sky vault with the sun paths on a plane. Some of them project it on the surface or a cylinder, others on planes parallel with the horizon. In principle there could be as many systems as map projections. However in architecture design , further investigations are based only on the so-called "sun path diagrams," because they have more advantageous characteristics than other systems.
The diagrams of the "sun path" system show the sky-vault projected on a plane parallel to the horizon plane. On the resulting. diagram the horizon line appears as a circle, and the sun-path as various curves depending on the method of projection and the proper latitude.
Recent methods of projection are the Orthographic, the Stereographic, and the Equidistant.
In the equidistant projection method the altitude angle appear on the diagram equally spaced. This characteristic assures equal readability for high or low angles, and makes plotting easy. A small circle facing the observation point will be flattened out into an ellipse-like figure when it is near the edge, one diameter remaining always the same, the other increasing
until it is π/2 times as great.
The diagrams of the "sun path" system show the sky-vault projected on a plane parallel to the horizon plane. On the resulting. diagram the horizon line appears as a circle, and the sun-path as various curves depending on the method of projection and the proper latitude.
Recent methods of projection are the Orthographic, the Stereographic, and the Equidistant.
In the equidistant projection method the altitude angle appear on the diagram equally spaced. This characteristic assures equal readability for high or low angles, and makes plotting easy. A small circle facing the observation point will be flattened out into an ellipse-like figure when it is near the edge, one diameter remaining always the same, the other increasing
until it is π/2 times as great.