Konica Minolta G600 instruction manual Short guide to photography, What is an Ev?

A short guide to photography

Photography can be a rewarding pursuit. It is a broad and disciplined field that can take years to master. But the pleasure in making photographs and the joy of capturing a magical moment cannot be compared. The guide is an introduction to some basic photographic principles.

The zoom lens not only affects how large the subject is in the picture, but it also influences the depth of field and perspective. Depth of field is the area between the closest object in focus and the furthest object in focus. As the lens zooms in to the telephoto position, the depth of field becomes shallower, sepa- rating the subject from the background. Many portraits are taken with telephoto lenses. Zooming the lens out to the wide-angle position makes both the foreground and background appear sharper. Usually landscape photographs take advantage of the large depth of field of wide-angle lenses.

Wide-angle lenses also create a strong perspective which gives a sense of depth in the image. Telephoto lenses compress the space between the subject and background and create a weak perspective.

What is an Ev?

Ev stands for exposure value. A change of one Ev adjusts the exposure by a factor of two.

+2.0 Ev	4X as much light
+1.0 Ev	2X as much light
Calculated exposure
–1.0 Ev	1/2 as much light
–2.0 Ev	1/4 as much light

54 A SHORT GUIDE TO PHOTOGRAPHY