TAPPI's Dirt Chart cards are manufactured from an original negative produced on CRR film. The cards are processed on a rapid-access processor using CUFD chemistry. Each card is produced on photographic paper via a contacting frame with an Olite light source and Olite light integrator which controls the specific exposure designated for accuracy and consistency. To ensure the accuracy of the charts, each piece is measured by examining the 2 dot with a 100 x magnifier that has a reticle (scale) incremented in 5/10,000mm. Card Stock. This OPAQUE chart is to be used with TAPPI Test Methods T213, T437, and T537.