|
Paul the odd shape can be explained by tiny amounts of backlash or overcorrecting while guiding. It is no coincidence that the elongation is a combination in RA and DEC directions. Try some shortish exposures of bright stars without guiding and at least you can eliminate this as a cause. If you are using the 80ED to guide at native FL (600mm) you will find it is marginal for the Vixen at 1200mm.
Bert
|