Well as I've been at home looking after my sick son, I've had a bit of time to do some more repros using DSS to modify the ratio of R, G & B when debayering my images. Elio has provided me with a link which will hopefully allow me to get a better determination of the ratios required.
Anyway, here are repros of M27 & NGC253 - the first image in each series is the new image...
