R72 Sayce Logarithmic Test Chart
This chart is a photographic image featuring 90 lines and spaces of gradually decreasing width in logarithmic series. The charts have a base length of 100mm and are supplied on 0.175mm thick ester-based film. Typically in use, the image is examined to determine the finest detail that can be distinguished. The finest resolved line is then counted to define the resolution of the device. Includes 6 charts, resolution table and for use.