Hi Mate,
I think the large image scale has real potential. The further the image can be spread over the sensor must help to minimise image break down. I guess the ideal if the mount tracked okay would be to fill the sensor with the image. Ofcourse then mount stability comes into it also.
I have got 3 extention tubes might give it a try tonight on the 14".
Asi if it looks clear tonight you can come out, I realise you don't want to go late.
