Indeed the hard power off approach is something that should be used.
However, and excuse me if it was unclear, this is not what is recommended here either. The hard power off is really removing the power plug during acquisition.
In this particular case, if I understand correctly, the acquisition is either a single shot (then the acquisition stops automatically) or a timelapse but once again this can easily be stopped by ptp commands.
But thank you for pointing out that you should never remove the power plug during acquisition. We see a lot of problems when users are doing so. The file system will be corrupted and a recovery will be necessary which will take time (and most of the time users don't know what is happening and are wondering why the acquisition is not starting).
- DO NOT REMOVE THE POWER PLUG DURING ACQUISITION
- ALWAYS STOP YOUR ACQUISITIONS either with the web interface, the press button or PTP commands.
- READ THE MANUAL to understand the colors of the LED which indicates the current status.