plt.rcParams['animation.ffmpeg_path'] = 'C:/ffmpeg/bin/ffmpeg.exe'
writer = animation.FFMpegWriter(bitrate=500)
anim.save('T:/baysestuaries/USERS/TSansom/Tiltmeters/testdeployment/tilt2.mp4',
    writer=writer, fps=8)
matplotlib animation movie: quality of movie decreasing with time