Thanks Rowland and Simon. Ambient temp was 23C, rather high for winter, must be global warming.
The temps never go much lower than 10C here anyway. The D70s is getting a bit long in the tooth also. It's a 2005 model I think so 9 years old now. It doesn't like ISO1600 (what the above were taken at) for longer than a minute. The frame becomes a sea of noise. ISO 200 and 400 are better with it but require tracking for the longer subs and a cloud free moonless night. What are those again?
I haven't seen noise reduction software that I like yet. They usually cost detail somewhere along the line.
Edit, just looking at the individual subs, they are quite well exposed, I could have probably taken the ISO back to 400 or 800. Nasty amp glow I have to contend with in the top left corner.