Size estimation charts are useful in a variety of circumstances for accurately measuring spots, inclusions, and defects on different textile surfaces, paper, plastic, etc. Other brand transparency charts may be imaged using a second generation copy from a master negative. Ours are first generation Master charts for increased accuracy. Produced on high dimensionally stable lithographic film, .007 stable base polyester photographic film. A densitometer is used to calibrate the imaging equipment as well as a certified hglass scale and an Edmund scientific 60 power microscope to measure each image.