The Tiger or Tigers addressed by this kit were coated with "Zimmerit" when in service. This should be added by the modeller for accuracy. Note that a few different patterns of Zimmerit were used on Tigers built at different times. The pattern is different again if the coating was added to upgrade a serving Tiger.
If the tank has been in battle, damage to its Zimmerit coating is likely.
The Zimmerit coating tended to weather off over a period of a few years. If you are referring to photographs of wrecked Tigers taken after the war, they will not give you a clear picture of how the vehicle appeared in service.