In part 1 I did manage to get tracking working but
when I looked at my images they were pretty well
useless so I gave up.
The first image which was just a 2 minute unguided
shot to see if everything looked OK showed clear field
rotation if you looked at the stars at the bottom of the
photo. They were long in shape and were clearly
rotating about some point in the photo. So they looked
like small arcs.
The next images with autoguiding for 30 minutes
were strange. The star images at the bottom left were
tilted towards the center of the photo and the stars
images at the bottom right were tilted towards the
center top of the photo as well.
Something like this:
/ | \
I would think that if my polar alignment was off,
they would be little arcs, no?
Here is some background:
The scope is on a 10" diameter pier, attached to a
16"x16" 5' deep concrete pillar that has a base that is
3' x 3' down at 5 feet.
I did this myself, and probably didn't compact the
earth around it enough but it's been 1 year since it's
been in place.
I did a PemPro polar alignment about 6 weeks ago,
and I got the alignment with everything locked down to
about 1 minute of arc from the pole. The last session I
did a month ago, had 8 30 Minute subs that were as
perfect as could be. SInce that time, the scope was
just parked and today I imaged the same object in the
same part of the sky as last time.
So, what could cause the slanted stars? Is my
polar alignment off? Does the polar alignment of a
permanently installed scope chan! ge with time and
temperature? It has gotten much colder lately and it
has been raining really hard for about a week, with some
days seeing 20mm of rain.
Should I just scrape the whole setup and take up