a hemispherical sensor, so strictly speaking, it does not directly relate to illuminance. Relationship of camera settings to luminous exposure edit The image-plane illuminance is directly proportional to the area of the aperture, and hence inversely proportional to the square of the lens f -number; thus HtN2;displaystyle Hpropto frac tN2 for constant lighting conditions, the exposure is constant. Gebele, original assignee: Hans Deckel, filing date: Nov 2, 1953, issue date: Apr 8, 1958 "Exposure value" indicates combinations of camera settings rather than the luminous exposure (aka photometric exposure which is given by ( Ray 2000, 310) HEt, displaystyle HEt, where The illuminance. Jones, Loyd., and. Restore original file time : OK Nothing patched! Exposure meter calibration is discussed in detail in the Light meter article. Properly, the meter calibration constant as well as the ISO speed should be stated, but this seldom is done. On most cameras, there is no direct way to transfer an EV to camera settings; however, a few cameras, such as some Voigtländer and Braun models or the Kodak Pony II shown in the photo, allowed direct setting of exposure value. The proper EV was determined by the scene luminance and film speed; it was intended that the system also include adjustment for filters, exposure compensation, and other variables.
Alien Skin, exposure, x2 (9 r / 35410 win x64 bit) For Exposure forexposure _txt) Twitter
See Use of apex values in Exif for additional discussion. EV and apex edit Main article: apex system The Additive system of Photographic EXposure ( apex ) proposed in the 1960 ASA standard for monochrome film speed, ASA PH2.5-1960, extended the concept of exposure value to all quantities in the exposure equation by taking base-2. The set EV could be locked, coupling shutter and aperture settings, such that adjusting either the shutter speed or aperture made a corresponding adjustment in the other to maintain a constant exposure ( Ray 2000, 318). Boston: New York Graphic Society.