The HOYA Variable Density II is an adjustable density filter that covers an ND range from 1.5 to 9 f-stops (ND3-400). The filter is equipped with a newly designed rotating frame that offers a convenient rotary knob for improved operation. For still images, a variable density filter allows the photographer to reduce the shutter speed according to their intentions when this is not possible due to camera limitations. When shooting video, it is important that the shutter speed matches the set frame rate, ideally twice the frame rate. By using a variable density filter, the shutter speed can be adjusted accordingly to achieve the natural and smooth motion desired in video footage, as shown in the image below.
