Hi Andy,
Please find the logs attached, together with the 2 FITS.
PHD2_GuideLog_2016-09-16_235411.txt (53.7 KB)
sg_logfile_20160916233335.txt (484.9 KB)
1. FITS (00:09 local time) with trailed stars with large swings in RA, after I increased the RA aggressiveness: https://drive.google.com/open?id=0B_pmhCQ1-e6aTlN5VDdqSUxvTEE
2. FITS (00:32 local time) with trailed stars after I turned on dithering: https://drive.google.com/open?id=0B_pmhCQ1-e6abmpkYzJsLWw3Qk0
I then uninstalled PHD2.6.2 and reinstall 2.6.1, and it worked better that night.
Please help.
David