I am still trying to figure out how to work software so I play with this and that..the color I see as secondary because I really cant see it... I am color blind and it shows..
However in the interests of sharing experiences so others may get an idea..
This is the biggest 30 sec stack yet...52
or a 26 minute exposure with perfect tracking

... the first try I left out a dark..the hot pixies danced across the image showing the mount to be so out over 30 minutes

..yet at 30 sec bites I was able to grab a fair bit of detail

..I substracted a dark from nights earlier and it worked thank goodness..
the center could be better (its recoverable) but I cant mask yet with satisfactory results in this softeware ..its me not it

.
Ran it thru noiseware for a silky finish
alex