Easily extend your long timelapse with GoPro Hero4 Black, Hero4 Silver, Hero3+ Black, Hero3+ Silver, Hero3 Black, Hero3 White, Hero 2 and Hero cameras, and some DSLR's, to well over 100 hours when a power point is not available.
You will need to set up your camera with an external battery and a device called an Intervalometer, which plugs directly onto the back of the camera, and will turn the camera off between frames., preventing power wastage when idle. This is all you have to do. Click this image for an expanded view:
All you will need is some common sense and the few components below:
1. An External 12V battery (See About Batteries). This will teach you everything you need to know about batteries and which is best for your application.
Your chosen battery could be as big as this or as small as you want. The length of the timelapse you can do depends on the size and the type.
2. A DC-DC Converter;
This device is going to convert your 12V supply to the 4.5 V needed to power the GoPro during your timelapse.
I use the Manson SDC-5203 1.5V - 12V Selectable DC-DC Converter because I can see the remaining voltage in my chosen battery and select any output voltage I require. (Device is available on eBay but not from the supplier.)
3. A Battery Eliminator (Also known as a DC Coupler).
This device is going to fit into the battery compartment in your GoPro to replace the internal battery. You will need to cut a hole in the bottom of a spare back to feed the power cable through, as in the second image below. I just cut the connector off the battery eliminator, added some extra cable and soldered it to the connector which plugs into the OUTPUT of the DC-DC converter.
DC Couplers are available from Cam-Do, on eBay, or from GoPro. Note that if you are going to waterproof it you will have to put silicone or some other sealant over the hole. I don't care - I use it in the upright position in pouring rain with no problems.
This device is the most important component in the whole project!
It fits on the back of the GoPro, inside the case. When programmed to your requirements it will turn the camera on, take a frame, then turn the camera off as you require. This means it is not using power between frames.The other brilliant innovation is that you can leave the rig in situ filming a timelapse, then come back weeks later, unplug the battery, connect a fresh battery and the intervalometer will continue its pre-programmed sequence without interruption. Absolute genuis!