Greetings Marc (Mr Multiweb!) I have a mask but had difficulty picking up the spikes on live view with APT. Because I found it easier to find and focus the star on Live View I have not really pushed using it. Should I instead take a series of focus shot exposures -i.e 10/20/30 sec etc and look for the diffraction spikes centralising on these?
Thanks to you (and all the IIS folks that keep advising us newbie types)
Graz