CASCAR: Clausthal All Sky Camera Recordings

This dataset contains approximately one million images taken from an all sky camera over five months. It has been collected by the Energy Informatics lab at the Department of Informatics at Clausthal University of Technology, Germany. Collection methodology The images were obtained using the OCULUS All-Sky Camera (150 degrees field of view) and the Oculus 180 Lens with ND Filter (No. 610-0024). Images were captured at a resolution of 800x600 pixels (WxH). The image acquisition process was scripted, such that the data collection was carried out during the time interval from sunrise to sunset; during this period, images were recorded at intervals of 5 or 15 seconds (see month-wise description below for details). The camera exposure time was dynamically adjusted (approximately hourly after the start of data collection) to adapt to changing light conditions. The data were collected in the city of Clausthal-Zellerfeld, Germany. GPS coordinates: 51.8067 N, 10.3575 E. Directory structure Each month's photos have been compressed into separate archives. Filenames of the collected photos have the following format: directories/YYYY-mm/dd/HHMMSS_Exp.jpg YYYY year (2024) mm month (05-09) dd day of month (01-31) HH hour (in 24hr format) MM minute SS second Exp exposure time in milliseconds (e.g. 120 = 120ms) Month-wise description of data The number of photos per month, their collection interval, and any periods where no data has been collected are given as follows: Month and year of collection Missing time periods (if any) Collection interval Number of photos May 2024 Data for days 01-05 have not been collected. Data on day 06 starts at 7.01pm. Data on day 16 ends at 11.40am. Data for days 17-20 are missing. Data on day 21 starts at 5.05pm. ~15 seconds (all days except for day 07) ~5 seconds (day 07) 79,132 June 2024 none ~15 seconds (days 01-27) ~5 seconds (days 28-30) 137,090 July 2024 Data on day 02 ends at 10.06am. Data for days 03-07 are missing. Data on day 08 starts at 4.42pm. ~5 sec 255,978 August 2024 none ~5 sec 293,569 September 2024 Data on day 26 ends at 7.42am. Data for days 27-30 have not been collected. ~5 sec 209,646 Total statistics Timeframe during which photos were collected 5 months Total number of days during which photos were taken 138 Total number of collected photos 975,415