Hello all...
Experimenting with dropping down to f8 last night with my 300mm f4L IS lens.
I find the aperture blade pattern on the brighter stars to be a bit obtrusive, but I love the tightness of the stars and detail in this short exposure. Colours are nice and bright too - I like this lens!
Canon 40D (modded)
Canon 300mm f4L IS @f8, IDAS LPS2 filter.
4x10 mins, iso1600, ICNR on.
Hope to get much more RGB and Ha to add to this soon

So no High Res as yet!
Doug