Telescope control and photometric reduction using AA8 scripts
Posted: 27 Dec 2022, 23:07
Thanks to AA8 I have the complete telescope control and data reduction pipeline in conjunction with Anaconda python, postgress database and DBeaver database creator / viewer.
There are 2 main AA8 scripts:
For each variable ~20 standard stars are auto selected in the FOV from the AAVSO APASS 128 million stars (using python and postrgress). Names, positions, magnitudes, mag errors of these standards are stored in a flat file for each variable and filter. My Planning Python code selects the variables in time sequence that are to be measured. There are many details how the python code works however the point is that the code creates the AA8 script for the entire night, including auto shutdown of the observatory. The results of the night are hundreds of FITS files which names include the variable, filter, date & time and a file with a list of all these FITS file names (and flats, dark flats and darks).
The second AA8 script is used to automatically measure all these FITS. For each FITS AA8 layers the appropriate darks & FLATS, reads the positions of the variable and standards and plate solves. The aperture size is selected based on FWHM (or can use the variable or brightest standard in an iterative process in the selection of aperture size to maximize signal to noise). The variable and standard’s ADUs and SNs are measured and written to a flat file. I then use Python code to do the final reduction to include single star single magnitude and ensemble transformed magnitudes with errors (B and V filters). The results are stored in a data table which can then be read to plot and create AAVSO input files.
The example shown is 2 nights of data on AB CAS that is an eclipsing variable with a delta Scuti as one of its components. Over 1600 FITS were reduced. THANKS FABIO!
There are 2 main AA8 scripts:
For each variable ~20 standard stars are auto selected in the FOV from the AAVSO APASS 128 million stars (using python and postrgress). Names, positions, magnitudes, mag errors of these standards are stored in a flat file for each variable and filter. My Planning Python code selects the variables in time sequence that are to be measured. There are many details how the python code works however the point is that the code creates the AA8 script for the entire night, including auto shutdown of the observatory. The results of the night are hundreds of FITS files which names include the variable, filter, date & time and a file with a list of all these FITS file names (and flats, dark flats and darks).
The second AA8 script is used to automatically measure all these FITS. For each FITS AA8 layers the appropriate darks & FLATS, reads the positions of the variable and standards and plate solves. The aperture size is selected based on FWHM (or can use the variable or brightest standard in an iterative process in the selection of aperture size to maximize signal to noise). The variable and standard’s ADUs and SNs are measured and written to a flat file. I then use Python code to do the final reduction to include single star single magnitude and ensemble transformed magnitudes with errors (B and V filters). The results are stored in a data table which can then be read to plot and create AAVSO input files.
The example shown is 2 nights of data on AB CAS that is an eclipsing variable with a delta Scuti as one of its components. Over 1600 FITS were reduced. THANKS FABIO!
