The Hoya Variable Density filter uses two polarizing layers to control the amount of light that passes through the filter and into the camera lens. At it's minimum effect the filter passes 1/3 of the light in a scene. That is equal to 1.5 stops on the aperture or shutter speed. At it maximum effect the filter passes just 1/400 of the light in a scene. That is equal to 9 stops on the aperture or shutter speed.
After the filter is mounted on the lens, turning the filter ring between "Min" and "Max" can greatly control the amount of light entering the lens. With the Hoya Variable Density filter it is possible to shoot with fast lenses like 50mm f/1.4 lenses wide open at f/1.4 in full sun for a very shallow depth of field. Or, to slow down the shutter speed to where the shutter can be open for several seconds in full sunlight. This is enough to create artistic blurring shots of motion on water, cars, people or almost anything that moves. The creative possibilities are endless.
The Hoya Variable Density filter uses high-quality optical glass from Hoya Corporation, the worlds largest optical glass manufacturer and is available in sizes 52mm to 82mm.
For best results Hoya recommends using a tripod when photographing at slow shutter speeds.
Reviewed by 2 customers
nice filter, very well made But you cant use your lens cap with it so i'm sending it back
At first everyone told me this was a begginers toy but the old square nd filters didn't fit my needs, so I decided to give this a try. I found that it suited all my needs. It eliminates the air gap between the front element and the first square filter, and or course the distortion of multiple overlapping filters. It takes some learning but the results are really good.