G'day Bart,
Yeah all shot on an old Gopro 3. The quality isn't great but it was really quite fun and simple shooting.
I used a simple U frame to mount the Gopro. To that I had a Sola 2000 light attached on a flex line. I mounted a cheap Gorilla Pod plastic tripod to get steady shots with the MacroMate lens from backscatter.
I found I lost a lot of good shots due to the Gopro being full auto. It would bump up the exposure when I shot against the dark substrate. The Spot metering I found worked sometimes but I gave up on it as the settings are a pain to navigate through.
I edited in the vignette for a couple reasons. The corner sharpness was very poor (not that the video is sharp at all), I found adding a vignette added some more feeling, bring more attention to the subject, solved corner sharpness and helped some of the shots blend better. I know some people don't like vignettes on video but its seemed better to my eye than without.
I'd really like to try out the manual setting on the 4, I feel it would perform much better with lighting. But I think I will wait for the Gopro 5 or perhaps save some cash for a real setup.