TimeTeleScope

The goal is to realize a time-lapse using a raspberry π and some python code and finally get this:

(This was done over 10 days, with almost each day an irregular session the morning and one in the evening)

data acquisition

This is well documented on the web and consisted in simply:

• setting up the raspberry π to use the camera
• create a startup script startup.sh (or clone this repo in /home/pi using git clone https://github.com/laurentperrinet/TimeTeleScope) consisting of the commands which take 2 successive frames at different exposures :

raspistill -rot 270 -ev -10 --metering spot -o /home/pi/Desktop/orchid/`date +%Y-%m-%d.%H:%M:%S`.jpg
raspistill -rot 270 -ev -8 --metering spot -o /home/pi/Desktop/orchid/`date +%Y-%m-%d.%H:%M:%S`.jpg

• run that script regularly (every ten minute) by adding the following line to the cron table (using sudo crontab -e):

*/10 * * * * /home/pi/TimeTelescope/startup.sh

image processing

Three notebooks to transform a sequence of frames into a movie:

• utilities to load images : A_load-images.ipynb
• histogram matching using different techniques (each runs A_load-images.ipynb first):
• B_equalize-histograms-laggui.ipynb (my first try)
• B_equalize-histograms-sklearn.ipynb (works best)
• using a mask : B_equalize-histograms-mask.ipynb (not great)
• putting things together : C_movies.ipynb (runs B_equalize-histograms-sklearn.ipynb first)