THE DEVELOPMENT OF THE PHOTOGRAPHIC OBJECTIVE 67 



a name refers to the "series number" of that particular lens. In the second column 

 is the /-number or range of /-numbers made, and in the third is the whole angular 

 field covered by the lens. In column four the range of available focal lengths is 

 stated. In the fifth column appears the diagram number illustrating the internal 

 structure of the lens and also, in some cases, the name of a well known member of 

 each type. This entry does not imply that the lens in question is a copy of the original 

 type; it may be an entirely independent design using radically different glasses and 

 radii of curvature, as has occurred, for example, in the Dynar and the Pentac, which 

 appear alike in a diagram but which are really quite dissimilar designs. 



In the last column appear remarks as to the purpose or uses of the various lenses. 

 A dash ( — ) in any column implies that the particular information was not available. 



Bibliography 

 Books: 



Von Rohr, M.: "Theorie und Geschichte des photographischen Objektivs," Springer (1899). 



Eder, J. M.: "Die photographischen Objektive," Knapp (1911). 



Mert^, W., R. Richter, and M. von Rohr: "Das photographische Objektiv," Springer (1932). 



Fhaprie, F. R-.: "How to Choose and Use a Lens," Am. Photographic Pub. (1937). 



Beck, C, and H. Andrews: "Photographic Lenses" (Beck; and Lund Humphries) 



Traill-Taylor, J.: " The Optics of Photography and Photographic Lenses," Whitaker (London) (1898). 



LuMMER, O.: "Contributions to Photographic Optics," Macmillan (1900). 



Gleichen, a.: "Theory of Modern Optical Instruments," H.M. Stationery Office. 



Neblette, C. B.: "Photography," Van Nostrand. 



Auerbach, F.: "The Zeiss Works," Foyle. 



Encyclopaedia Britannica, 11th ed., Photography, by A. H. Hinton. 



Periodicals: 



Clay: R. S.: Traill-Taylor Memorial Lecture, Phot. J., 46, 458 (1922). 



Kingslake, R.. The Development of the Photographic Objective, J. Optical Sac. Am., 24, 73 (1934). 



Taylor, W., and H. W. Lee: The Development of the Photographic Lens, Proc. Phys. Sac. (London), 



47, 502 (1935). 

 (See also a series of articles on current German lenses in Photo Woche, May to October, 1937.) 



