13
The StarShoot G4 can cool the CCD
to about 25°C below the ambient
temperature. But remember that the
ambient temperature changes and you
want to have enough cooling capacity
to take dark frames at the same
temperature later.
To set the cooler:
1. With the G4 already connected
to your computer, plug the 12V
power source into the G4’s power
port. The fan will immediately
power on.
2. Click
Connect in the Camera
Control tab if you have not
already done so.
3. Click
Cooler On, and the CCD
temperature will begin to drop.
4. Enter a target temperature for
the CCD in
Target (°C), and
remember you can only cool
to about 25°C cooler than the
outside air temperature. The
CCD temperature will naturally
heat up on its own. To start with,
set the
Target (°C) to about
20°C lower than the current
CCD Temperature, to allow
yourself some margin for outdoor
temperature changes. (
Figure 12)
5. Let the camera temperature
stabilize. You can resume imaging while this takes place. It’s common for the
CCD temperature to fluctuate to within about 1°C of your target temperature.
You can view the
Temperature Log (Figure 13) to monitor the status of the
cooling system. Go to the
Camera menu, and click Temperature Log If the
cooler power remains at 100% after 20 minutes, you need to reduce the target
temperature. Most of the time you can simply monitor the CCD temperature by
looking at the
CCD Temperature in the Camera Control tab.
Note: Being able to match the light and dark frame temperature is more impor‑
tant than trying to cool the CCD more than the TEC will allow. Matching the dark
frame temperature to your light frames ensures a very effective calibration to
remove unwanted noise from your images.
Figure 12.
Monitor the CCD temperature
and determine the best target temperature
to set.
Figure 13.
The temperature log can help
you determine how much margin you have
to cool the camera based on the cooler
power and current CCD temperature.
