Hi RAGIII,
yes I should have mentioned the photos - but there are so many.
Here are the best:
page 3; no 14 page 5; B17, 4/1, 4/11 (for re-painted Udet), 5/2, 6/2, 6/16, 11/8,11/15, 11/26, 12/5, 12/15, 13/3, 14/31, 15/9, 19/3, 19/11, 19/15, 53/1.
In many, if not most these cases, the demarcation is hard, independent of illumination and often continues around the leading edge - not an lighting/photographic artifact. Something to do with both material and paint application different from linen undersides.
Cheers,
GrahamB