Python script to display the Quality Imaging Hours on a given date.

Quality Imaging Time is a concept developed by Charles Bracken. In order to take astrophotographs a dark sky is needed. Astronomically, it means the Sun must be well below the horizon, the Moon shouldn't interfer too much (ideally, it should be also below the horizon) and the imaged object should be at least at 20° above the horizon to prevent atmospheric extinction. Apart from atmospheric conditions and light pollution, these conditions can be calculated using the observer location, date and time, and of course, the object itself.

This utility shows whether the sky is dark or not for each given date and location. It displays one of three possible conditions, every 30 minutes: dark sky, Moon above horizon or dusk/dawn/day.

This script needs Python 3 and PyEphem library.

• Fedora: python3-pyephem
• Ubuntu: python3-ephem
• SuSE: python3-ephem

Using the command line:

./python3 qitime.py --lat <latitude> --lon <longitude> --date <yyyy-mm-dd>

Quality Imaging Time
= Observer
  Date:2020/2/20 00:00:00       Lon:-15:25:00.0 Lat:28:00:00.0
= Rise/Transit/Set
  Sun   Rise:2020-02-20 07:33:24.000003 Transit:2020-02-20 13:15:25.000003      Set:2020-02-20 18:57:48.000003
  Moon  Rise:2020-02-20 05:32:03.000003 Transit:2020-02-20 10:53:10.000003      Set:2020-02-20 16:15:41.000003
= Twilight
  Quality       Dawn:2020-02-20 20:00:38.000003 Dusk:2020-02-20 06:30:36.000003
= Dark night (without any Moon)
  Darkness (Quality)    Start:2020-02-20 20:00:38.000003        End:2020-02-20 06:30:36.000003
  00  01  02  03  04  05  06  07  08  09  10  11  12  13  14  15  16  17  18  19  20  21  22  23   Moon phase
  🌌🌌🌌🌌🌌🌌🌌🌌🌌🌌🌌🌌🌘🌘🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌞🌌🌌🌌🌌🌌🌌🌌 🌘

• Víctor R. Ruiz

This project is licensed under the MIT License - see the LICENSE.md file for details.