Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision | |||
| en:ost:fokus [2016/11/10 23:10] – ↷ Links angepasst weil Seiten im Wiki verschoben wurden rhainich | en:ost:fokus [2016/11/10 23:12] (current) – [Aperture diaphragms] rhainich | ||
|---|---|---|---|
| Line 64: | Line 64: | ||
| Aperture diaphragm proofed to be a very useful assistance in finding the best focus and in testing the quality of the telescope imaging-capabilities. Aperture diaphragm with two apertures are usually called Scheiner diaphragm, whereas aperture diaphragm with more than two apertures are denoted as Hartmann diaphragm. The aperture diaphragm are mounted before the Schmidt plate. | Aperture diaphragm proofed to be a very useful assistance in finding the best focus and in testing the quality of the telescope imaging-capabilities. Aperture diaphragm with two apertures are usually called Scheiner diaphragm, whereas aperture diaphragm with more than two apertures are denoted as Hartmann diaphragm. The aperture diaphragm are mounted before the Schmidt plate. | ||
| - | [{{ labcourse: | + | [{{ ost: |
| For finding the focus, the telescope needs to be pointed to a bright light source (e.g. a bright star). Several images of the light source are recognizable in case the telescope is defocused, since the light rays from the different apertures of the diaphragm pass through different points of the focal plain. The distance between the different images of the light source can be reduced by adjusting the focus. The optimal focus has been reached when the different images are aligned. | For finding the focus, the telescope needs to be pointed to a bright light source (e.g. a bright star). Several images of the light source are recognizable in case the telescope is defocused, since the light rays from the different apertures of the diaphragm pass through different points of the focal plain. The distance between the different images of the light source can be reduced by adjusting the focus. The optimal focus has been reached when the different images are aligned. | ||