I did a lot of experimenting yesterday and indeed, if I set the gain to sub 10, I get that "mask" of pixels in the image, not sure of the "science" behind that, but setting gain to 20 eliminated that issue.
My second mistakes was indeed over exposing so that the G,B histogram would fill out, it makes for a lovely bright image with a nice orange tint, but it's entirely wrong.
I found that setting the following helped:
Exposure (ms) 0.250
Got me 75% peak in R and sub 6% in G,B - though ideally I should aim for 0%
Of course you're both right, the camera really isn't suited to this kind of work if I am looking for resolution and an easier time.
Looks like I shall have to once again save some pennies! Though for now, I can still get images and enjoy those fantastic proms!
Thanks +Kevin Franklin
and +Paul Stewart
The bank manager however refuses to send his thanks :P