The photos are in B/W and not colour. There is no way to take as evidence colours from B/W photos. The two ships below are in the same light green/blue camouflage. One shows up black and the other light. As you can see guessing colours based on tones is not valid. True, the photos pre-date the 1936 order by one year, however I would say Dark Sand/Light Sand are considerably more likely than colours based on tones in B/W photos.