White Balance is such an important function to photograph taking, and can bring you a true and creditable picture. As well as we know, the white balance of the camera or DV sometimes can not be modulated just follow the will. This lens cap can solve all these problems easily which fits both DC/DV cameras. Ways of getting white balance: 1.Set the manual mode for white balance. 2.Attach the lens cap on the top of the lens. 3.Set the focus length to telephoto mode. 4.Aim at the scene of photo source. 5.Keep the white balanced value. After modulating the white balance, remove the cap and you can take better pictures.