LOL Marc, cheers mate, glad you liked it!

I had to make my count 5 posts so I thought I'd be a comedian while I was at it!
Using PS, you basically downstep opacity of your layers in lighten mode. I was frustrated at first I couldn't figure out how others were doing it then I found This article(
http://www.davidkinghamphotography.c...ke-star-trails) by David Kingham who ironically was frustrated too. LOL! I cheat nowadays(as David mentions is possible) and use Steven Christenson's Advanced Stacking Action(
http://blog.starcircleacademy.com/advancedstacker/) which includes an option to save output after each step(....with intermediates) then I just stack output sequence into a timelapse. Original inspiration for it was a video by Dan Newton(
http://www.liquidinplastic.com/)
It dawned on me one day/night...wonder what would happen to a storm sequence if stacked

...