@gary, thanks for the kind words as always. Getting rid of the dead space on the left would probably be a good idea but I'm not so keen on square photos so I think that this shot probably can't be saved in that way - I'll think about that for next time though.
It's funny that both comments mention fill-in flash as this is something that I never remember to do. Using the onboard flash I've never managed to successfully that a shot that wasn't the usual extreme flash in the face type. Since reading your comments though I've tried using it, adjusted to a low power, as a bit of fill and I think I've cracked it - so many thanks for the prompt to get out and try it. I like taking photos in my conservatory as it's nice and bright (but not as cold as outside!) and there's sufficient distance behind the subject to get the background out of focus. It means that the light is generally behind the subject though so maybe I should manufacture some sort of large reflector to use as an alternative to flash.
@TinaC, I'll have a better play with the contrast on the next shot I do. I generally tweak the levels to get the blacks black and the whites white but I don't normally alter the contrast with respect to colour - I'll definitely give it a go though. Thanks for commenting.