Last night I was able to test my Teleskop Express field flattener on my Vixen FL102S and it seems to be just fine. So it has been effective on two scopes with quite different focal lengths and f ratios.
I thought I would then try to get the comet Garradd next to the Coathanger asterism. I just got focused and ready to start shooting and the cloud rolled in
Having cleared away and on shutting the dome it seemed to be clearing, so set up again.
This was just 13 x 2mins with darks (but I forgot to do flats) with my Megrez 90
In Deep Sky Stacker I was unable to stack on the comet (it just wouldn't recognise it?) so it is stacked on the stars. Fortunately any blur on the comet is not too noticeable.
You do not have the required permissions to view the files attached to this post.