Hands-on sky experience

Hands-on sky experience is a short movie for digital planetaria. It shows real images of real sky obtained with a 180° field of view fisheye lens, which is not exactly the same as we would see with naked eyes. In front of the audience, summer, autumn, winter and spring constellations exchange during one year, with a musical accompaniement of Antonio Vivaldi's Four Seasons. Observed in Kralovéhradecký and Pardubický regions, especially at places with small light pollution. The instrument used Canon 250D APS-C 24.1Mpx, lens Sigma 4.5mm f2.8 EX DC Circular Fisheye, exposure 8 s, stop 2,8, sensitivity 3200 ISO. Processing with programs Gmic, Gimp, Sequator, FFmpeg and Blender.

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As a preview, we prepared static circular images in full resolution, which should be projected onto a hemisphere tilted by 17°. Objects appear distorted, but if a visitor sits in our planetarium in the middle of the auditorium, the geometry of the resulting image is without distortions.


The movie is prepared in Full-dome 4K format (i.e. 4096 × 4096 pixels resolution), with a frame rate 25 fps. It is possible to download a ZIP archive with individual images (dome masters), which are to be converted for a given projection system (including a suitable gamma correction). We use a system delivered by Carl Zeiss Jena, with five Velvet projectors - each having 2560 × 1600 pixels, native contrast 1 : 2.5 million and special lens for a projection onto a spherical screen. We should emphasize this is a really large file, which is located at the WWW server of the Astronomical Institute of Charles University:

We also offer an audio track (and an alternative one) in Dolby Digital 5.1 format:

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