Lee resin filters are made from lightweight optically polymeric materials which makes then touch easy to handle and they can be wiped clean every filter is individually hand made by skilled technicians and is the passed through a rigorous quality control system to ensure 100 accuracy and consistencya real blue filter to add realistic colour to flat skies and is available in three strengths 1 being the most subtle to 3 being the strongest graduated filters feature an area of colour at one