Appendixes
108
Glossary
Metering
The metering refers to the way in which the camera measures the
quantity of light to set the exposure.
MJPEG (Motion JPEG)
A video format which is compressed as a JPEG image.
Noise
Misinterpreted pixels in a digital image that may appear as misplaced
or random, bright pixels. Noise usually occurs when photos are shot
with a high sensitivity or when a sensitivity is automatically set in a dark
place.
Optical zoom
This is a general zoom which can enlarge images with a lens and does
not deteriorate quality of images.
Quality
An expression of the rate of compression used in a digital image.
Higher quality images have a lower rate of compression, which usually
results in a larger file size.
Resolution
The number of pixels present in a digital image. High resolution images
contain more pixels and typically show more detail than low resolution
images.
Shutter speed
Shutter speed refers to the amount of time it takes to open and close
the shutter, and it is an important factor in the brightness of a photo, as
it controls the amount of light which pass through the aperture before it
reaches the image sensor. A fast shutter speed allows less time to let
light in and the photo becomes darker and more easily freezes subjects
in motion.
Vignetting
A reduction of an image’s brightness or saturation at the periphery
(outer edges) compared to the center of the image. Vignetting can draw
interest to subjects positioned in the center of an image.
White balance (color balance)
An adjustment of the intensities of colors (typically the primary colors
red, green, and blue), in an image. The goal of adjusting the white
balance, or color balance, is to correctly render the colors in an image.