firstly I had trouble figuring the category for this. If there is a better one let me know.
This guy took the popular Raspberry Pi (tiny computer), and put it inside a battery grip, connecting it to his DSLR. Because it's a computer and connected via usb, he gets access to the memory storage and if the camera has it then also the shutter and control/interval shots.
He is doing it with a Canon 5D Mark II.... but if it's possible, I'd love to develop something similar for The GH2 I have... Wireless tethering being my interest.
It is interesting, but it is no way an easy project.
Agreed it is difficult, however depending on money, you could solve it much easier. For example, he has it mounted in a battery grip. You could also buy a battery to power it properly (you can possibly also use a an actual phone charger, look for ones built to help charge an iPad).
If the Pi itself had internet access (via your phone or the event), it could be uploading to a lan server or the internet as well... but that stuff should be obvious.
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