The Functions Of The Temperature Control Box - Baader Planetarium SUNDANCER II Manual

8. As soon as the control box is powered, it automatically heats the lter up to the
necessary operating temperature. The display shows the temperature difference
to the set point; when the value 0 is shown, the lter is ready for operation. After
about ve minutes, the temperature control has stabilized and you can ne-tune it
if necessary (see the following chapter "Filter calibration").
9. While the lter heats up, you can can insert an eyepiece, point the telescope at the
sun and observe. Due to the longer focal length caused by the telecentric, the sun
must be positioned exactly so that it can be seen in the eyepiece.
10. The micrometer screw tilts the etalon a maximum
of 3° from the optical axis. This has two functions:
(1) You can check the setting of the H-alpha line
without changing the temperature of the lter. To
do this, turn the micrometer screw sensitively and
without using force clockwise all the way in, as
far as it will go, or close to that position, and the
H-alpha structures on the sun should be clearly
visible. The scale itself is only for orientation, the
stop does not have to correspond to the 0 position.
(2) The micrometer screw is used for fast Doppler-event observations: For example,
if a prominence is moving quickly towards you, this may be enough for the H-alpha
line of that structure to shift so far into the blue part of the spectrum that you need
to readjust – this can be done quickly and easily with the micrometer screw, by
decreasing the temperature, which takes a little bit more time, but keeps the lter
in the ideal tilting angle.
Note: After about three to ve minutes the lter is in temperature equilibrium, before
that slight changes in the image are possible due to readjustment.
Note: Observe the operating temperature of 0 to +40° C. At lower temperatures, the
lter must be thermally insulated so as not to overload the heating.
Note: The SunDancer II is pre-calibrated. To match it to your speci c system, you may
have to change the operating temperature slightly. Without further calibration, it may
show the best image when the micrometer screw is not in the most inward position.

The Functions of the Temperature Control Box

Once the lter has been correctly calibrated to your sys-
tem (see chapter Calibrating the Filter on page 16), you
only need to connect the temperature control box to the
SunDancer II and then to a 12V power source. The elect-
ronics will then bring the lter up to operating temperature
and automatically switch it off if it becomes too warm.
The display of the control box shows the difference from
the factory set temperature. If your particular setup requi-
res a different operating temperature, please refer to the
chapter "Filter calibration" for instructions.
As soon as the display shows a stable "0", the lter is
ready for operation. When the telescope is pointed at the
The micrometer screw can tilt the filter
to easily observe the blue wing of the
The display shows the temperature
difference to the ideal operating
temperature. Above shortly after po-
wering up, below once the operating
© Baader Planetarium GmbH | 2021
H-alpha-line
temperature is reached
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