Cokin Double Exposure B 346 square filter

With the Cokin Filter A346 Double Exposure you can expose the image in two parts so that you can combine two shots in one photo. One half of the filter is completely black and blocks all light transmission while the other half is completely transparent. During the first exposure, one half of the image remains unexposed. By rotating the filter 180 degrees you can then expose the second half of the image using the multiple exposure function on the camera.