Thanks Leon,
I've been keeping an eye out for you ( on the road and at work - thought you might pop in on your way up North).
I was stunned after the fact cause I matched the sound with the ....well whatever it was. And yes it was what you could say 'smokey'. The vapour trails on both were quite distinct...almost glowing.....
I should add that to the observation.
"Smoke like vapour trails, dispersing rapidly with a very faint glow"
I can image whist at work only cause it is quiet at the moment ( and it's a grave yard shift I do twice a week). I can see my camera through the window at one spot and the other is on an enclosed terrace but outside with no access for others so I can leave it alone doing its time lapse thing. So I might spend 5- 10 mins setting up then go back to work
.
[Safe travels Leon, and if you get to Broome go to Gantheume point and take some sunset shots ( or even Cable beach) . Very stunning !!!!]
Bartman