When buying paint made up to a specified colour, make sure that the full quantity of paint needed is purchased in one order. Slight variations can occur when adding the colour pigment, even over a short time.
Always thoroughly stir the paint befo-re using it. In case the pigments have separated out while it has been stored. In addition. If the paint has had to be made up in two or three tins, do not use the tins individually. Mix the contents together in a large container so that any colour variations that may occur between the tins will be blended.