ExpoDisc 2.0 - The Original White Balance Filter for Digital Cameras Gets Even Better Set white balance, meter for exposure, and dust map your sensor with the only calibrated and certified 18% transmission incident light metering filter. ExpoDisc 2.0 introduces user-selectable Warming Filters (gels) and an improved mount. ExpoDisc Saves Time Editing White Balance in Photos and Video When used to set a custom white balance, the ExpoDisc consistently produces excellent color in natural, artificial, and studio lighting, and it even excels in difficult mixed lighting environments. Easier to use than a gray card, white card or calibration target, simply place the ExpoDisc in front of your lens and capture the incident light while setting your camera’s custom white balance. For most cameras, this procedure takes only about 15 seconds. Whether shooting in RAW or JPEG, using the ExpoDisc to white balance your camera saves valuable time in photo editing software.