I am interested to read about this exposure system, but I can't able to get proper reference for this topic. If any one have materials to study on this, Please let me know.
APEX—The Additive System of Photographic Exposure is explained in detail by an abstract written by: Douglas A. Kerr Issue 7 August 4, 2007 ABSTRACT The Additive System of Photographic Exposure (APEX) provides for stating several factors involved in photographic exposure in logarithmic form. In this way, calculation of the “proper exposure” for a given situation may be done manually using only addition. Although the importance of that has largely faded since the time the system was developed, the scheme is still widely used in technical work relating to photographic exposure, especially the quantity “exposure value” (EV). This article explains the APEX system, and gives cautions about irregularities in its usage that are often encountered. INTRODUCTION
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