And finally here is the 30" single frame that has been stretched.
http://www.astrobin.com/full/250500/None/
I am thinking the short 30" subs are enough given the way they stretch, and the clipping is not there (see the Astrobin histogram on the detail page here:
http://www.astrobin.com/250500/
).
So a stack of these 30" subs will be my next effort I think. PS: remember the moon was up when these were shot.