The Solar Projector - AstroMedia
Pre-cut AstroMedia cardboard kit for a projection device for observing the sun without danger.
This handy device allows several people to observe sunspots, planetary transits and eclipses at the same time in comfort and without any danger. Thanks to sophisticated optics, the gaze falls only on a projected image of the sun, so no solar filter is needed.
The principle
The solar projector uses the principle of the camera obscura ("pinhole camera"), with which solar eclipses were observed as early as the 11th century and which is still used today in every camera: Light falls through a small opening into a darkened chamber and creates an upside-down image of the outside world on the opposite side. Instead of a simple aperture, the solar projector has a lens and convex mirror that together act like a Galilean telescope and provide high magnification, and a plane mirror redirects the image into a comfortable viewing position.
The optics
The optics consist of a double-lens glass achromat with a diameter of 30 mm and a focal length of 250 mm, which can be stopped down to 12 mm in five steps, an interchangeable optic with 2 convex mirrors with focal lengths of -10 and -14 mm respectively, and a plane mirror made of acrylic glass.
Easy to operate
The solar projector is very easy to operate: It sits on a Dobsonian base and can be adjusted to any elevation between 0° and 90°. Two integrated quadrants make it possible to determine the altitude of the sun. The size of the sun image is either 75 or 55 mm and can be viewed comfortably at right angles to the incident sunlight - very practical when the sun is high in the sky!
You can find an illustrated construction report here.
| Aspiration scale: | Medium |
|---|---|
| Time Line: | 2,0 Hours |
pre-cut and printed construction cardboard
for assembly
8 x DIN A4
with detailed assembly instructions
included accessories:
various mirrors and achromatic objective lens
Dimensions of the assembled item:
approx. 18.5 x 26.5 x 25 cm (W/D/H)
Der Sonnen-Projektor - Deutscha firm, flat work surface
€27.50
€26.13
€24.75
€23.38