I turn the RPi on and off as needed. The battery pack lasts a long time. The problem is that I have no way to tell the RPi to stop taking photos. Once way was to turn off the camera. The problem is that when I would turn the camera back on I was forgetting to disconnect the RPi from the USB, and boom ... before I could compose my imaged the RPi would trigger another batch of captures. So ... I turn the RPi on/off as needed to allow me to compose between captures.

The crontab is straight forward. However, I found some Python code that may help me start up my script at boot time similar to a system service.