The Back Focus Chart & White Balance Card by Vocas is a handy tool combining a focus chart, white balance card, and framing guide. It is useful in the field for checking and adjusting back focus on professional video cameras with interchangeable lenses. The details are printed on a 3mm thick foam board that measures A2 size.
As a white card, it is used to adjust the white balance of video cameras to the different color temperature of light in changing locations. The framing guide can be photographed as an aid in post-production to establish the aspect ratio for the project.