Upload & Sell: On
Orbs .. basically a torch on end of a rope swung carefully in same arc (not easy) whilst you rotate around a fixed spot.. Shutter kept open during this time .. helps to have darkness (very little ambient) . Once the Orb is done we quickly drew a bird with another torch as painting with light.
Practice...practice and practice..
Give it a go.. I think there are plenty of sites, videos online showing you what to do..