Tanker-Builder
YES, Boys and Girls.The paint out of the Bottle, Tube or other container are ideal specifications, NOT what should be used on the actual model. YOU must, Like the museums do-Adjust for scale and lighting!
Not really. There is no "must" do for painting in the hobby. Some brands do adjust for scale, and some of us like our paints as they look from the bottle or tin. Besides, with most any weathering technique in use, the end color will not be the same as when it's first applied to the model. Not to mention that not every paint manufacturer's paint is an exact match to the government paint standard color chip in the first place. There are way too many variables in play to say that modelers must do certain things in every case of painting.