Thanks all

Yes, Bert, there was some light pollution. I can just see the SMC naked eye, but only just, and thats at its highest. I had to remove some gradient too, it was slightly brighter towards the bottom, again, caused by light polution being stronger lower down. I had no trouble focussing your lens, I focussed by eye, took a short test image, then moved the foucus slightly to the left a few mm, then tried again and was luck, it was in sharp focus. So much light comes in at F2.8 I only need to go for 4 mins each at ISO 200 otherwise its too much fogging. Imaging with this lens at a really dark site doing up to 10 minute subs would be fantastic I think.
I used the Iris function "Dynamic Stretching" and also some "colour stretching" to bring out the faint stuff but not burn in the bright areas like centre of 47 Tuc, with a bit of trial and error these functions can work really well. I always save the original unprocessed image and if I muck up the processing, just open the original and try again.
Scott