90
7 The Astronomical Detector
Fig. 7.7 The above figure illustrates a bias frame loaded into FITS Liberator. The Median and
StdDev figures required are highlighted
as notes about the camera and software used in addition to any problems you may
have encountered. Your report should include the following:
1. A description of the shape of your curves and an interpretation of how the curves
vary with exposure time and temperature?
2. What was your bias level? How does the bias vary with temperature and internally
across the CCD?
3. How does the dark current vary with the exposure time and temperature? (Don’t
forget that there is a bias in your dark, so you need to subtract the effects!) How
does the dark frame variation across the CCD compare to that of the bias frame?
4. How significant is the dark current when compared to the bias current, and how
might we deal with both the additional counts caused by the bias and dark and
their associated uncertainties?
7.5.2 Practical 2: Flat Frames
In the second practical you will be taking flat frames. Flat frames are a vital part of
the calibration process and are the calibration frame type that needs to be updated the
most often. As you will see, they are also a primary contributor to uncertainties. In
7 The Astronomical Detector
Fig. 7.7 The above figure illustrates a bias frame loaded into FITS Liberator. The Median and
StdDev figures required are highlighted
as notes about the camera and software used in addition to any problems you may
have encountered. Your report should include the following:
1. A description of the shape of your curves and an interpretation of how the curves
vary with exposure time and temperature?
2. What was your bias level? How does the bias vary with temperature and internally
across the CCD?
3. How does the dark current vary with the exposure time and temperature? (Don’t
forget that there is a bias in your dark, so you need to subtract the effects!) How
does the dark frame variation across the CCD compare to that of the bias frame?
4. How significant is the dark current when compared to the bias current, and how
might we deal with both the additional counts caused by the bias and dark and
their associated uncertainties?
7.5.2 Practical 2: Flat Frames
In the second practical you will be taking flat frames. Flat frames are a vital part of
the calibration process and are the calibration frame type that needs to be updated the
most often. As you will see, they are also a primary contributor to uncertainties. In