I am an owner of an amateur point and shoot camera (a Canon S120) that has a 'Star' mode (time-lapse with a minimum interval between shots of 60s). It's a nice thing and I enjoy using it, but I have a problem with the length of the resulting video as the camera dies as I get about 4~5 seconds of the time-lapse. There is no way to set a smaller intervals between shots so I wonder how I can make these lapses be taken for a longer period of time?
The standard battery is pretty tiny and features only 1060 mAh, another battery I have for it is battery pack NB-6L that features 1500mAh and slightly better, but still does not do the trick. I tried to find out ways to connect it to an external power source but failed. Another solution might be to do with software as if there is a way to set time intervals between the shots to, let's say, 30 seconds, that would practically produce longer time-lapse videos that would be slower of course.
Can this issue be worked around with this camera? I know that it can be done with more high-end gear.