Quote:
Originally Posted by Ross G
A beautiful photo Bert.
Amazing detail.
Great composition.
Ross.
|
Thanks Ross. I think I have finally got all the alignment and flexure problems under control. The last? to be solved was the differential expansion/contraction on hot 30C+ days which was throwing out alignment as the system cooled down. It was just a matter of always unlocking the longitudinal dovetail that holds the ITS (image train stabiliser) frame after a night of imaging. This then allows the whole image train to expand and contract without putting any stress anywhere which can change the alignment.
The sensor can be adjusted to about 10 micron or less at the corners from perfect othogonal alignment by adjusting the ITS. It needs to be this good to get almost perfect stars to the corners. The hot days and cool nights can play havoc with this crucial alignment.
It is a lot of pain but the results make it all worthwhile.
Bert