WHAT IS AN EV?
Ev stands for exposure value. A change of one Ev adjusts the exposure calculated by the camera by a factor of two.
+2.0 Ev | 4X as much light |
+1.0 Ev | 2X as much light |
0.0 Ev | Calculated exposure |
1/2 as much light | |
1/4 as much light |
LIGHT SOURCES AND COLOR
The human eye adapts itself extremely well under different conditions. The paper of this manual you are reading looks white regardless of the type of lighting. Photographic systems are much less flexible. As the light source changes, so does the overall color of a scene - fluorescent office ceiling lights create a green cast to pictures, regular household tungsten light bulbs make everything red. Like your eyes, the camera’s white- balance controls adjust for different lighting to make natural looking pictures.
The most common source of light, our sun, changes color depending on the time of day and the atmospheric conditions. The sun is of course very warm near the horizon and very blue at noon. The daylight preset
Artificial lighting is more consistent but will show variations. Tungsten lamps become warmer as their wattage decreases. And fluorescent lamps come in classifications that define their color. The preset white balance settings can be adjusted with the rear control dial (p. 70) to match the change in these light sources.
Some artificial lighting have a discontinuous spectrum that create very unnatural color in a photograph. White balance cannot correct
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