ExpoDisc, the original white balance filter 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
Whether shooting in RAW or JPEG, photographers using ExpoDisc to white balance their images save valuable time in photo editing software. 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
The ExpoDisc is far easier to use than any 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. Using an ExpoDisc custom white balance will virtually eliminate the need for RAW or JPEG post-capture colour adjustments.
The ExpoDisc is not just for white balance, though. The precision calibration and uniformity of the ExpoDisc means that it can also be used to meter for an 18% incident exposure and to produce a dust map of the image sensor.
To meter for an 18% exposure, stand at the subject's position and aim the camera back towards the intended shooting position. Use the camera's meter as seen through the viewfinder to adjust the aperture, shutter speed, or ISO until a proper exposure is indicated. It's also possible to make exposure adjustments based upon the position of the histogram spike on an ExpoDisc test shot. Simply adjust the aperture, shutter speed, or ISO until the spike is centred.
ExpoDisc 2.0 Neutral and Portrait White Balance Filter 77mm