Image acquisition with the MU script
Customizing the MU script
Image shifts for producing binned calibration files
' IMAGE SHIFTS FOR PRODUCING 2x2 BINNED CALIBRATION FILES
shiftX1 = 3 ' These 4 parameters may need to be adjusted to obtain a
shiftX2 = 1 ' perfect alignment between the 2x2 binned calibration files
shiftY1 = 1 ' produced by this script and 2x2 binned images taken at the
shiftY2 = 0 ' CCD camera. Their values are usually small integers.
' ShiftX1 and ShiftX2 are horizontal shifts, while ShiftY1
' ShiftY1 and ShiftY2 are vertical shifts
The 2x2 binned calibration files produced by MU are not taken with the CCD
camera; instead, they are generated by averaging the values of 2x2 blocks of adjacent pixels in
the full resolution calibration files (which are taken with the CCD camera).
This procedure was adopted because there is often not enough time during twilight to take
a sufficient number of both binned and unbinned calibration files.
This section contains four integer parameters shiftX1,
shiftX2, shiftY1, and
shiftY2 which may need to be adjusted to obtain a perfect
alignment between the 2x2 calibration files produced by MU and 2x2 binned images taken
at the CCD camera (which will be calibrated using the binned calibration files produced by MU).
The values of these four parameters are usually small integers.
shiftX1 and shiftX2
are horizontal shifts, while shiftY1 and
shiftY2 are vertical shifts.
The recommended method to determine the values of the four shift parameters is described below:
- Take a 2x2 binned dark frame manually with MaximDL CCD, and save it to disk.
- Configure MU.cfg to take dark frames immediately after
the script is started (without waiting until sunset), using
the following parameter values:
- Start the MU script (click here
for detailed instructions).
- After MU finishes taking and processing dark frames (at that point
the ACP console will say that the script is waiting for a target list),
interrupt it by clicking the
Alert() button in ACP, and
answering the questions which will follow by clicking the
- Open the binned dark frame Dark_bin2_0001.fit
(created by MU) in MaximDL. This dark frame will be in a subdirectory
named \yymmdd_telescopeName\dark or
\yymmdd\dark inside directory
yymmdd represents the UT date of the next nighttime
observing run and telescopeName is the telescope's
name as defined in parameter
- Open the binned dark frame you took manually in MaximDL.
- Compare the location of hot pixels or other recognizable features
which are fixed on the CCD detector between the two dark frames. If they coincide on
the two dark frames, your values of the four shift parameters in MU.cfg
are correct. If they do not coincide, change the values of the shift parameters in
MU.cfg, delete the subdirectory containing the dark frames produced
by MU, and go to Step 3 above. Note that if the features in the two dark frames are located on the
same columns (rows), then the values of
shiftX1 and shiftX2
(shiftY1 and shiftY2)
are correct and need no further adjustment.
Weather station parameters
' WEATHER STATION PARAMETERS
weatherStation = True ' True to use a weather station
weatherStationType = "generic" ' The only currently supported station is "generic"; see the
' TAO documentation for details
weatherReportFile = "c:\wxReport.txt" ' File containing latest weather report
maxReportAge = 10. ' Maximum acceptable age (min) for the latest weather report
- weatherStation. Set this parameter to
True if there is a working weather station connected to one of the
computers on the observatory's local network, otherwise set it to
False. The weather station is supposed to provide air temperature
measurements which are used to focus the telescope when a
focus-temperature relationship has
- weatherStationType. This parameter specifies your
weather station model. The only currently supported weather station model is a "generic" one
(specified as generic), which produces temperature reports
in the format described below. Please
contact the author about adding support for other
- weatherReportFile. This is the full path of a text file
containing the latest weather report produced by the weather station. This file is supposed to
be frequently updated by some external program which reads the weather station output. For the
"generic" weather station, the first line of the weather report file should provide the
temperature in the format
The temperature information may be located anywhere on the first line of the weather report file.
The weather report may also contain other information, such as the values of other
Note: Even if your weather station is not "officially" supported in MU, its output
may be read by the script, provided you have software which is capable of producing report files
where the temperature is provided in the above format. Please contact the
the author about adding support for other weather
- maxReportAge. This parameter specifies how old (in minutes)
a weather report may be in order to be considered "current". Reports which are older than
maxReportAge will be ignored by the MU script.
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© 1999-2004 Paulo Holvorcem