This photo of Rolls Royce armoured cars http://digital.nls.uk/pageturner.cfm?id=74549474 is the one I was talking of in another thread. If you look closely, there are 3 Rolls Royces, and the front one is in splinter pattern camouflage whereas the two nearest the camera are just one colour.
Great find, oirob, thanks again.
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In wine there is wisdom, in beer there is freedom, in water there is bacteria.
Found two of the Renault autocanon photos on the IWM site - it was the 26th April 1918, in the Battle of the Lys, and the British troops are the 18th Middlesex Regiment