m108 and a load of clouds blew in.

[Fraunhoffer]

30-04-2019 : My first attempt putting a gpcam into the back of a c8. (with a focal reducer)

The sky eventually cleared around 1:30, despite the weather forecast saying is had been clear from 9pm(!). Ursa Major had rotated around to a slightly less neck breaking position to the west and was well away from the London light dome so I decided to continue my Messier Quest. 
m108 is near the bright star Mirak and I had worked out that 1 turn of the RA slow-mo and a 1/3 turn of the dec slo-mo would bring it to the centre of view. A faint smudge of a line was nearly dead centre, so I popped in the gpcam385 and repeated the routine taking the advantage of Mirak to focus the camera with a Bahtinov mask first.
The camera was connected to Sharpcap and by cranking up the gain to max the galaxy revealed itself on the screen. I then spent a few minutes centering it up. The galaxy takes up nearly the whole fov on this little camera which has about 11'x20' on this set up.
At this point I realised I had not used the 'smart histogram' to suggest a camera setting so I guessed at a gain of 1000 and 15s exposures with live stacking and alignment selected. All seemed well , the galaxy was starting to appear on the screen, so I left the camera and went indoors to put the kettle on and visit the small room.
I came out a bit later to find a thin wisp of cloud had blown over into my shot so I hurridly saved the stack and went to look at Jupiter.
The resulting  image had just 56 frames (840s) had a nice streak of 'fog' across it , but the galaxy was underneath. This is the final result.
I've had to really play with this in PaintShop pro using a mask to clear out the fog.

Overall I'm pretty pleased with the unguided movement of the mount.(EXOS-2 with RA drive)
I also realised I had not selected the dark frames to subtract - hence the noise in the lower right corner. (I need to do a checklist as Im forgetting to do things at 2 in the morning)

Celestron C8, gpcam385, Antares focal reducer, Celestron prism diagonal, EXOS2-unguided, Sharpcap gain=1000, exp=15s, 56 exposures live stacked.