Thank you all for your comments and input.
There is definatly more detail in it which I discovered while processing. I decided to go with a subtle image as is the case with the majority of my images. I'm assuming the quality of the capture is what stops me being able to extract more without ruining the quality of the final product. I do intend to run it through Pixinsight at some stage ( this was with Photoshop ).
I have come up with a very similar result as you did Andy with your app but I backed out of it because I didn't like the texturing of the additional detail. Certainly not offended by others including yourself having a play with the image though. I'm hoping that's why we are on this site, to help each other discover what's possible. So thank you for taking the time to give it a crack