Unless you are painting direct from the yard and absolutly no weathering, ships paint will fade over a relitivaly short amout of time. Ships operate in the harshest environment imaginable for something made out of steel. Salt, wind, waves and constant sun will turn the "perfect color" to something that looks off from what the original manufacturer had in mind. You can put two ships from the same class and built from the same yard together and see a difference in shade depending on how far apart in time they left the yard.