Nikon 28-80MM Instruction Manual - Page 123

ISO film speed The international standard for representing film sensitivity. The higher the number, the greater the sensitivity, and vice versa. A film speed of ISO 200 is twice as sensitive as ISO 100, and half that of ISO 400 film . Vignetting Progressively diminished illumination on the film from the center to the corners. There are two kinds of vignetting-natural vignetting caused by the lens, and vignetting that is caused by improper use of accessories such as a lens hood or filter. Metering system See the column on page 32. Rear-Curtain Sync Flash fires an instant before the second (rear) curtain of the focal plane shutter begins to move. When slow shutter speeds are used, this feature can create a blur effect from the ambient light, i.e., flowing-light patterns following a moving subject with subject movement frozen at the end of the light flow. (See "Front-Curtain Sync".) Slow Sync A flash technique for using the flash at a slow shutter speed . Flash shooting in dim light or at night at a fast shutter speed often results in a flash-illuminated subject against a dark background. Using a slower shutter speed with the flash brings out the background details in the picture. The N751N75QD's Slow Sync mode extends the automatically controlled shutter speed range down to 30 sec. (in Auto-Multi Program, Aperture-Priority Auto) or 1 sec. (in t:::I Night Portrait mode). 123