Innovation Special Planetariums 9 - Carl Zeiss Planetariums

The new Planetarium in Radebeul
Ulf Peschel, Head of Radebeul observatory
and planetarium.
30 Innovation Special Planetariums 9, 2012
When the sun sets in the planetarium,
slowly sparkling stars and the softly
shimmering band of the Milky Way
populate the dark blue sky, and the
beholder is immersed in a world far
away from the shrill and hectic routine
of everyday life. It is the peace and quiet
of a night in the mountains or in the
endless expanse of a lonely desert, or
the fairy-tale ambience of a Scandinavian
forest. The planetarium shows us a
sky that amazes and surprises us with its
magnificent beauty.
The Dome Matadors
I first saw the Radebeul Planetarium
from the inside in 1976 as a member
of the Young Astronomers’ Working
Group. At that time, at the center of the
dome there was an ZKP 1 projector by
Carl Zeiss. For us guys it was enormous
fun when, unobserved, we could turn
the daily cycle onto full speed, lean back
in our seats, look up, and literally get
butterflies in our stomachs. That went
on until a little man in his mid-seventies
came into the room, gave us a reprimanding
look, and then got down to
brass tacks, or, more accurately, to the
stars in the sky of the evening in question.
From this moment on we were
totally spellbound and listened attentively
to his every word, for he explained
things with such devotion and such
knowledge, with highly accurate wording
that described the celestial bodies
and their motions to the fullest possible
extent. Everything about him perfectly
matched a presentation about the stars,
and nothing was reminiscent of today’s
planetarium shows. I wonder whether
today he would still find his public in
the Planetarium. That first projector was
followed by a ZKP 2 with a reasonable
night sky and significantly expanded
representation options compared to
its predecessor. Operation was simple
and clear. After 27 years of service, the
instrument was literally worn out, and
a new one had to be acquired. It was
clear that the replacement should be
an opto-mechanical projector, as digital
systems are unsatisfactory, especially
when it comes to star representations.
Night sky par excellence
For the last six months, a SKYMASTER
ZKP 4, the latest development from Carl
Zeiss, has been operating in the dome of
the planetarium. The first impression of
the sky dome is overwhelming. The stars
appear to be small points, sharply imaged
over all areas of the projection surface
onto a jet-black background. The
celestial bodies get their light only from
a high performance LED. The instrument
at Radebeul is the first worldwide
to be equipped with this technology.
The brightness gradations are very fine.
Many important stars are shown in their
natural colors. What is very pleasant
is that the colors can be clearly identi-