Jan Erik Vallestad:
The reducer is 99.99% the reason for this. I went through the exact same thing a couple of months ago and got some invaluable help from another member who also had been through the same. In short I got rid of the reducer which was fine with smaller sensors (and perhaps NB) but after that no issues at all. Imaging at F/10 I have been using 60-120s mostly. But yeah, unless you can guide/track at 0.38" average you will need to bin in post. I downsample x2 in Pixinsight which works fine.
If you want to look at my thread click here.
Ty for posting the link very interesting
