Hello all,
I just thought I would enlighten you about the final results of the saturation issue.
Jack Flesher has been very helpful indeed. I sent a few RAW files directly to him to examine on his computer, and the result is that there is two sides to the problem. One is that my camera was underexposing slightly, which of course increases colour depth, but there also is a saturation issue, and more so with the orange-red tones. Both these things we have agreed upon, but what doesn't make sense is why we have had 3 different backs have the same issue, and Jack has not reported any such issue with the backs he has used.
My dealer has sent some sample images to Phase One for assessment, but I haven't heard any results yet. My solution (thanks to Jack) has been to modify in Capture One's colour editor a camera profile to fix the problem, which I now use. So yes the issue has been got around, but it would be nice to know the real cause.
Again, thanks Jack for your assistance!
Regards,
Geoff Ross