| 摘要 |
<p>PURPOSE:To perform adequate exposure easily by finding exposure correction coefficients for reciprocity law failues and flares characteristic to camera previoulsy by experiments, by storing them in a central arithmetic processor electronically, and by selecting an exposure correction coefficient. CONSTITUTION:The proper exposure time of a photoengraving camera for full- scale photography is denoted as T0, and then its proper exposure time T for optional magnification (m) is calculated by T=[(1+m)/2]<2>P.T0, where P is a correction coefficient. The photoengraving camera is provided with a central arithmetic processor 15 which stores many said P values corresponding to various photosensitive materials and other various conditions and outputs a required P value at need. For this purpose, a P value which corresponds to photographic conditions is selected with a button on a console panel 6 and outputted to set the proper exposure time T corrected by the P value, thus obtaining adequate exposure easily.</p> |
