Appendixes
98
Glossary
ISO sensitivity
The sensitivity of the camera to light, based on the equivalent film
speed used in a film camera. At higher ISO sensitivity settings, the
camera uses a higher shutter speed, which can reduce blur caused by
camera shake and low light. However, images with high sensitivity are
more susceptible to noise.
JPEG (Joint Photographic Experts Group)
A lossy method of compression for digital images. JPEG images are
compressed to reduce their overall file size with minimal deterioration of
the image resolution.
LCD (Liquid Crystal Display)
A visual display commonly used in consumer electronics. This display
needs a separate backlight, such as CCFL or LED, to reproduce
colors.
Macro
This feature allows you to capture close-up photos of very small
objects. When using the macro feature, the camera can maintain a
sharp focus on small objects at a near life-size ratio (1:1).
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.