Hi Carl,
Looks like a glancing reflection off anodized Al (or perhaps other metal) somewhere in the camera body or OTA. I had a similar problem with my OTA a few years ago.
See this post from 2013, it shows the diffraction spectra caused by a bright star outside the FOV:
http://www.iceinspace.com.au/forum/s...2&postcount=31
Regards,
EB