After another session last night I think I am on top of what’s going on now. The expected diffraction pattern is very apparent when you look at it through an eyepiece. When I was looking at it on screen via the camera I evidently did not have anywhere near enough exposure/gain. In consequence I was only seeing what I suppose is the brightest “1st order” pattern alongside the target star. With more exposure the camera is now recording the 2nd & 3rd order (and beyond) patterns. Why it takes until the 2nd order pattern to ‘settle down’ I do not yet understand. I shall try and discover why.
Alan.
British Astronomical Association
Supporting amateur astronomers since 1890
