PySQM is a multi-platform, open-source software designed to read and plot data from Unihedron SQM-LE and SQM-LU photometers, giving as an output files with the International Dark Sky Association (IDA) NSBM Community Standards for Reporting Skyglow Observations. (http://www.darksky.org/night-sky-conservation/248) PySQM is distributed under GNU GPL, either version 3 of the License, or (at your option) any later version. See the file LICENSE.txt for details. This software has been developed by Mireia Nievas (UCM) with the invaluable help of: Jaime Zamorano (UCM), Laura Barbas (OAN) & Pablo de Vicente (OAN)
"PySQM the UCM open source software to read, plot and store data from SQM photometers"
Nievas Rosillo, Mireia and Zamorano, Jaime (2014) UCM eprint (PDF)
How it works
In a first step, the program tries to connect to the SQM photometer and takes some 'tests' measures (metadata/information, calibration and data) to check that the device is working as expected. After that, the program begins data acquisition. In every iteration, it checks whether it is night-time. In that case new data is taken. Every N measurements, the main program calls a plotting function to generate a graphical representation of the current nightly data.
After downloading the software, you need to modify the file pysqm/config.py. In this file you will find several variables that need to be configured to match your hardware settings. For example:
- Location of the observatory (geographical coordinates).
- Device identifier.
- Device address (either IP address for SQM-LE or COM/ttyUSB port).
- Location of the data files.
- Axis limits for the plot.
Remember that python (2.7) syntax is mandatory in this file.
How to run the software
After configuring the software, make sure you are in the parent directory were the README, LICENSE and MANIFEST files are located > ls LICENSE.txt MANIFEST.in README.txt pysqm setup.py And then run the software.
<> python -m pysqm
The program should find your SQM device and the data acquisition.will start (if it's night-time). In some systems, where python3 is the default version of python, you need to specify python2 as the interpreter to use. This is done usually running it as:
> python2 -m pysqm
> python2.7 -m pysqm
Note: running the setup.py script is neither tested nor necessary at the moment. The program is currently being redesigned as a normal python package, but at present no setup is required.
Or use the pySQM.exe stand alone program.
Please let us know if you are using it. Suggestions are wellcome.
Rubén Díez Lázaro explains how to set up a Raspberry Pi based monitor station
More info including known issues, FAQ and troubleshooting in PySQM info page