Attached is a crop of 7 images stacked (non aligned) that shows a consistant drift. The elongations are consistent across the entire field. they all go the same way, there is no rotation, curvature or distortion to suggest non alignment of optical train. It is interesting to note that the elongation is worse when i am zenith and imaging west.
Polar alignment is as good as i can get, strar remains perfectly centred in crosshair east, west and zenith for over 12minutes. My PHD guiding graph shows that i am accuratley guiding.
I'm guiding with a separate small modified findersope/guidescope (not an OAG) and imaging thru an ed120 refractor.
The elongations are visible in 1 minute and 4 minute exposures.
I cant upload the original RAW files as they are too big for IceInSpace so if you can assist please go to:
http://filez.bordermail.com.au/sj8y78t
and download the zip file.
Any assistance will be greatfully appreciated
Regards
Carl Rainer