Sánchez Brea, Luis MiguelTorcal Milla, Francisco JoséBernabeu Martínez, Eusebio2023-06-202023-06-202007-08-011. G. C. Holst, CCD Arrays, Cameras, and Displays (Society for Photo-Optical Instrumentation Engineers, 1996). 2. P. Hariharan, Optical Interferometry (Academic, 1989). 3. J. W. Goodman, Introduction to Fourier Optics (McGraw-Hill, 1996). 4. W. K. Pratt, Digital Image Processing (Wiley, 1978). 5. International Standardization Organization, Guide to the Expression of the Uncertainty in Measurement, Geneva (ISO, 1995). 6. E. W. Weisstein, "Root-mean-square," From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/Root-Mean-Square.html. 7. S. Lai and G. Von Bally, "Fringe contrast evaluation by means of histograms," in OPTIKA '98: 5th Congress on Modern Optics, G. Ákos, G. Lupkovics, and P. András, eds. Proc. SPIE 3573, 384-387 (1998). 8. L. M. Sánchez-Brea, J. A. Quiroga, A. García-Botella, and E. Bernabéu, "Histogram-based method for contrast measurement," Appl. Opt. 39, 4098-4106 (2000). 9. R. Christiensen, Linear Models for Multivariate, Time Series, and Spatial Data (Springer-Verlag, 1985). 10. N. A. Cressie, Statistics for Spatial Data (Wiley, 1991). 11. L. M. Sánchez-Brea and E. Bernabéu, "On the standard deviation in CCD cameras: a variogram-based technique for non-uniform images," J. Electron. Imaging 11, 121-126 (2002). 12. L. M. Sánchez-Brea and E. Bernabéu, "Estimation of the standard deviation in three-dimensional microscopy by spatial statistics," J. Microsc. 218, 193-197 (2005). 13. P. Bevington, Data Reduction and Error Analysis for the Physical Sciences (McGraw-Hill, 1969). 14. E. Keren and O. Kafri, "Diffraction effects in moire deflectometry," J. Opt. Soc. Am. A 2, 111-120 (1985).1559-128X10.1364/AO.46.005027https://hdl.handle.net/20.500.14352/51179© 2007 Optical Society of America. The authors thank Tomás Morlanes for his valuable ideas. This work has been supported by the “Codificación óptica de la posición a escala nanométrica: Nuevas tecnologías y dispositivos ópticos” project (DPI2005-02860) of the Ministerio de Educación y Ciencia of Spain and the “Tecnologías en ecología, alta precisión y productividad, multifuncionalidad, y tecnologías de la información y comunicaciones en Máquina Herramienta” CENIT project of the Ministerio de Industria, turismo y comercio. Sanchez-Brea is currently contracted by the Universidad Complutense de Madrid under the “Ramón y Cajal” research program of the Ministerio de Educación y Ciencia of Spain.We present a technique for determining the contrast of an intensity distribution in the presence of additive noise and other effects, such as undesired local amplitude or offset variations. The method is based on the variogram function. It just requires the measurement of the variogram at only four points and, as a consequence, it is very fast. The proposed technique is compared with other standard techniques, showing a reduction in the error of the contrast measurement.engjournal articlehttp://dx.doi.org/10.1364/AO.46.005027http://www.opticsinfobase.orgopen access535Standard-DeviationÓptica (Física)2209.19 Óptica Física