Nice Wayne! You can turn down the gain and do shorter subs. Looks like a fair bit of star saturation. This camera has fairly low read noise.
When using just a UVIR filter I use unity gain (90) and do about 2min subs. That's about optimal for reducing the influence of read noise. Shiraz even made a table for it
http://www.iceinspace.com.au/forum/s...=160444&page=2