It's a funny fact that Green can go Blue, Black, or Yellowish Green, depending on conditions. Then if you add in the mix of colours used in camos, you can grasp the problem.
I'll always remember the argument about Brunswick Green. When we repainted a loco in Precision Paints, a manufacture of exact repro paints.
Anyway, repainted the loco, rolled it out of the paint shed, only to receive lots of comments that the colour was far too light, That's not the right colour, who ordered the wrong colour, and so on.
Guess what. After about 3 weeks in service, and cleaning with a traditional oily rag, we started to get comments that the engine looked superb, and the colour was spot on!
So, who was right?