ST-7 Dark Current as a Function of Temperature
A series of ST-7 Dark Frames are shown here to illustrate the effects of lowered temperature on Dark Current.
This image is composed of swaths from four different dark frames of 20 minutes duration.
- The swath on the left was taken at -20C
- The next swath was taken at -30C
- The next was taken at -40C
- The swath on the right was taken at -50C
In the winter when outdoor temps run around +10F I am able to run my ST-7 at almost -40C
In the summer when outdoor temps run around +40F I am often unable to reach -20C
The dark noise is the primary limitng factor on the ST-7's ability
to run for long exposures and I am actively seeking ways of cooling the ST-7 in order to be able to reach a temp of -40C all year around. The addition of an extra TEC stage seems promising.
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