The B+W 49mm Cross Screen 4x Filter is designed to be used perpendicular to a point light source such as the sun, a light bulb, or a candle. Within the filter's surface is a combination of fine, etched line types that help to create a starburst effect with four primary diffraction spikes that extend from the light source.
This filter is most effective for pictures where the light source used to generate the starburst effect is a highlight with a significant degree of contrast from the rest of the image. The B+W 49mm Cross Screen 4x Filter is constructed from optical glass for clarity as well as color fidelity, and features an F-Pro brass filter ring for durability as well as jamming prevention. The filter ring can be rotated in order to adjust the direction of the diffraction spikes and overall orientation of the starburst effect.