Great Photo Peter and I must say I have really enjoyed your essays.
All I have worked out is I need a better computer to manage more subs
My lap top has been stacking flat out for near two days...so long I have lost track of time.
So for me it seems I will need to take longer subs in any event because of the limitation placed on me by deep sky stacker.
I only have 8 gig of ram...
I took your advice of varying iso ...anyways trying yet another stack smaller si hopefully I get something that justifies the time I have spent.
Alex