MerlinPete : looks as though the roundels have been re-touched or doctored in some way on your photos : are the originals like that? and sagindragin, the tone of the rudder is very similar to that of the roundel red and on the fin flash in published photographs I have in a few books on the shelf. The red was almost a ‘brick red’, possibly a little more muted,than your example, but colour and tonal differences can be somewhat objective. The photos I’ve seen of RN241 as in the photographs above show sharper definition of the fuselage roundel with standard yellow surround ,blue white and red inner.