Changing The Operation Temperature; Using A Neutral Density Filter - Baader Planetarium SUNDANCER II Manual

sun, it takes about three to ve minutes for the lter to reach temperature equilibrium.
The lter has a temperature sensor that switches off the heating if the lter becomes
too hot. In this case, the heating element is automatically switched off and will not
be reactivated until the lter has cooled down to 25 °C and the control box has been
disconnected from the mains.
To switch off, simply disconnect the temperature control box from the power source.

Changing the Operation Temperature

You can easily change the temperature of the lter and thus the position of its transmis-
sion window. Increasing the temperature shifts the maximum to the longer-wavelength
red wing of the H-alpha line; decreasing it shifts it to the blue wing in the shorter-
wavelength spectral range. A change of 10.0 units shifts the transmission maximum by
about 1 angstrom, which is also the maximum possible change.
Press the up arrow to increase the temperature or the down arrow to decrease it.
After a few seconds, the display changes to the current value and the lter is tempered
to the new setpoint (displayed as a deviation from the factory-set temperature value).
The new setpoint remains stored. So the next time you use it, the control box will
always show the last set value.
Note: For quick observations in the blue wing of the H-alpha line, you can also use the
micrometer screw. By turning the micrometer screw, you can also check if the lter is
tuned to the H-alpha-line or if the contrast can improve.
The difference in brightness between the prominences and the solar disk is very large,
and it can be helpful, especially when observing with a large exit pupil, to screw a neu-
tral density lter into the eyepiece. This makes the structures on the solar disk more
visible to the eye, while the prominences become less
visible. You can achieve the same effect with a single
polarising lter that you screw into the eyepiece.
Then, as when used with a Herschel prism, the image
brightness can be adjusted by rotating the eyepiece
in its eyepiece clamp.
How strong the effect is depends on the respective
system as well as on your own eyes. In principle, the
image brightness can also be adjusted simply by
increasing the magni cation; however, this presuppo-
ses that the air turbulence permits higher magni ca-
tions at all.
We recommend the following lters:
• Polarising lters: 1¼"
• Neutral density lters (grey lters) ND 0.6 (T=25%): 1¼"
• Neutral density lters (grey lters) ND 0.9 (T=12.5%): 1¼":
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Manual: SunDancer II

Using a Neutral Density Filter

# 2408343; 2" # 2408342
Polarizing and Neutral Density Filters dim
the brightness, which may lead to better
visibility of details in the eyepiece
# 2458343; 2": # 2458321
# 2458344; 2": # 2458322