Blooming CCD Camera

Computer says no blooming (after 300s)

While waiting for the clouds to clear, or the mist at least, I decided to see if I can make my CCD chip on the QHY8L bloom, which means over exposing the image so that electrons leak from the wells on the chip and drain off into other parts of the chip.  Apparently the QHY8L has anti-blooming - not sure how it works, but a 300s exposure of Arcturus might do the trick.
Lets try 600s.

This is pointless.  If the camera can't do 10 minute exposures of a bright star without blooming, then I have really bought a dud.  The guiding went AWOL during the exposure, so this will be interesting...  PHD (guiding) has gone off the scale again, so I've left the last minute to the mount to guide.

Not what I expected, little zig-zags...