Hmm - difficult to tell Andy.
I've played around with the colour balance and contrast, and also changed the pic to monochrome, adjusting the contrast, and couldn't see any definite demarcation on contrast change in the colour(s).
However, the nose area around the cowling certainly looks darker, so it's possible that there is a splinter pattern, although I'll admit it does seem to be all one colour.
Is there any evidence of the Arado being finished in a single upper surface colour ?