PHOTOGRAPHIC SENSITOMETRY 207 



straight line, the reproduction is free from distortion, whereas the degree of distortion 

 is proportional to the curvature of this characteristic. 



By studying the various steps represented in the four quadrants, we are able to 

 determine what change in photographic technique and processing is required in order 

 to minimize tone distortion. 



Bibliography 



Periodicals: 



Mees, C. E. K., and S. E. Sheppard: Instruments for Sensitometric Investigations, Phot. J ., 44, 200 



(1904). 

 and : The Sensitonietry of Photographic Plates, Phot. J., 44, 282 (1904). (Contains 



excellent bibliography.) 

 Wallace, R. J.: On the Sensitiveness of Photographic Plates at Different Temperatures, Astrophys. J ., 



28, 39 (1908). 

 Mees, C. E. K.: Effect of Humidity on the Sensitiveness of Photographic Plates, Astrophys. J., 40, 



236 (1914). 

 Harbison, G., R.: Characteristics of Photographic Materials in the Ultraviolet, J. Optical Soc. Am., 11, 



341 (1925). 

 Jones, L. A., and O. Sandvik: Spectral Distribution of Sensitivity of Photographic Materials, J. 



Optical Soc. Am., 12, 401 (1926). 

 Harrison, G. R.: Instruments and Methods used for Measuring Spectral Light Intensities by Photog- 

 raphy, J. Optical Soc. Am., 19, 267 (1929). 

 TuTTLE, Clifton: A Recording Physical Densitometer, J. Optical Soc. Am., 26, 282 (1936). 

 Roberts, Creighton: Photographic Determinations of Film Strip Exposures, Am. Phot., 533 (1937). 

 Pitt, F. G. H.: Measurement of Specular Density, Phot. J., 486 (1938). 

 KoERNEB, A. M., and Clifton Tuttle: Standardization of Photographic Density, Phot. J., 739 (1938). 



J. Soc. Motion Picture Engrs., 19, 739 (1937). 

 See also the many papers published in the Journal of the Optical Society of America and the Journal of 



the Society of Motion Picture Engineers. 



Books: 



Hardy, A. C, and F. H. Perrin: "Principles of Optics," Chap. 11, McGraw (1932). 



"Motion Picture Laboratory Practice," Eastman Kodak Co. (1937). 



FoRSYTHE, W. E.: "Measurement of Radiant Energy," Chap. 8, McGraw (1937). (Contains excellent 



bibliography.) 

 Neblette, C. B.: "Photography Principles and Practice," 3d ed.. Van Nostrand (1938). 



