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Manual: SolarSpectrum H-alpha-Filter and Baader Planetarium Telecentric Systems
Setting the Temperature
The working temperature of the filter and thus the position of the central wavelength
can be adjusted via the control box. This serves on the one hand to calibrate the filter
to your individual system (see the following chapter "Filter Calibration"), and on the
other hand for finetuning to observe the red or the blue wing of the H-alpha line. For
observations in the blue wing.
To change the working temperature, perform the following steps:
1. Wait until the filter has reached its target temperature and displays the numerical
value "0", or the target and actual temperatures are the same. Give it some time, so
that the whole area of the filter ist at the same temperature
2. Press once UP
or DOWN
to get into the programming mode. The display of
the target temperature starts to blink. Press UP
to increase the temperature, or
DOWN
to decrease it. Confirm he new value with SET; if you are using the cont-
roller type with one display, the value will be used automatically if you don't press a
key for a couple of seconds.
3. Although you can change the value by up to 10°, but only a small change is neces-
sary for a visible change.
Increasing the temperature results in a ahift of the wavelength towards the longer
wavelengths in the red part of the spectrum. On the other hand, decreasing the tem-
perature moves the central wavelength towards the shorter wavelengths in the blue
part of the spectrum. In the blue wing of the H-alpha-line, you can observe fast, high-
energy changes on the surface of the sun.
The new value is also stored when you cut the power supply.
Please note:
The filter temperature is influenced by the incoming heat of the sun. If
the filter wasn't pointed at the sun for some time, the temperature needs some time
to compensate for the additional heat of the sun once it is pointed onto the sun again.
After about 30 to 60 seconds (depending on the filter diameter) it will be back to the
desired wavelength.
