ISO 15739 Noise and Dynamic Range Testing: The Grayscale Step Chart, SNR, and OECF
ISO 15739 is the international standard for measuring the noise and dynamic range of digital cameras, using a grayscale step chart of patches with known density. The mean of each patch builds the OECF and the standard deviation gives the noise, from which SNR and dynamic range follow. What the standard measures, reflective versus transmissive charts, the visual-noise metric added in the 2023 edition, why uniform illumination is the make-or-break, and how ISO 15739 complements ISO 12233 as the other half of image quality.