The GF Technology Fluorescence Filter is a top-of-the-line lens filter that is perfect for those who want to create high contrast pictures with wavelength control. The fluorescence filter blocks UV and violet light below 400nm, while allowing light above 400nm to pass through. This results in enhanced contrast and sharpness in your images. All in all, this filter allows you to easily adjust the amount of light that is let in, making it perfect for a variety of different usage applications.