Twin filter kit containing a hoya multi coated uv and a hoya slim circular polarising filter ultra violet uv rays although invisible to the human eye can cause a hazy bluish cast in photography the multi coated hoya uv filter effectively eliminates uv light of wavelengths shorter than 370nm to give clearer images with more neutral colour balance no exposure compensation is necessary use of this filter is recommended in most situations as a full time lens protector but especially when p