Star trail taken over a mountain hut in Buskerud, Norway.
Made from 19 images f4 ISO 200 - set at 5 min image, 5 min 1 sec interval.
Under testing - f2,8 was giving almost daylight on the ground, f5,6 was too dark.
It should have been a far longer trail - the plan was for 5 hours worth - but at 4 hours I noticed that the moon was swinging round and nearly into shot - so I headed out and found that both the main battery and the battery grip battery had drained in the cold. A hazard of -10C photography :)