many thanks all.
Rodger, I too was surprised as Id taken care to get the alingment quite close. The first couple of subs had trailing even though I could see the guiding was going well. I also noted I was having to occaisionally make DEC corrections northwards. The dec shaft was at about 45% altitude, so I split the difference and slightly moved the mount very slightly to the left in azimuth, and also slightly higher in altitude. The dec corrections required were then much less and the stars no longer trailed. I was wondering it it was tube flexure, or just polar alingment that just wasnt accurate enough at the start. If it was tube flexure then perhaps the change in polar alingment was offsetting it.
yes youre right I always though objects near the equator show the largest error and thus thats the best place to do drift alingment, I cant really explain it, except to be prepared to re-adjust polar alingment when imaging close to the SCP even if Im convinced its right to start with.
I guess its called the gray planetary as like most nebulae it isnt bright enough to see colour in.
Thanks, Paul Ive not got that list saved.
Scott
EDIT: heres a full res. crop
