glossary
JPEG (.jpg) Joint Photographic Experts Group. Popular image compression
fi le format used for images destined for the World Wide Web.
Key light Main light source relative to lighting ratio.
Landscape Horizontal format.
Latitude Image sensor’s ability to record the brightness range of a
subject.
Layer A feature in digital editing software that allows a composite
digital image where each element is on a separate layer.
Layer mask A mask attached to an adjustment layer that is used to defi ne
the visibility of the adjustment. It can also be used to limit the
visibility of pixels on the layer above if that layer is grouped or
clipped with the adjustment layer.
LCD Liquid Crystal Display.
LED Light Emitting Diode. Often used in the camera’s viewfi nder to
inform the photographer of the camera’s settings.
Lens Optical device used to bring an image to focus at the image
plane.
Lens angle Angle of lens to subject.
Lens hood Device to stop excess light entering the lens.
Levels Shades of lightness or brightness assigned to pixels.
Light The essence of photography.
Light meter Device for the measurement of light.
Lighting contrast Difference between highlights and shadows.
Lighting ratio Balance and relationship between light falling on subject.
Long lens Lens with a reduced fi eld of view compared to normal.
Low key Dominant dark tones and shadow densities.
Luminance range Range of light intensity falling on subject.
Macro Extreme close-up.
Magic Wand Tool Selection tool used in digital editing.
Matrix metering Refl ected meter reading averaged from segments within the
image area. Preprogrammed bias given to differing segments.
Maximum aperture Largest lens opening, smallest f-stop.
Megapixels More than a million pixels.
Memory card A removable storage device about the size of a small card.
Meter Light meter.
MIE Meter indicated exposure.
Minimum aperture Smallest lens opening, largest f-stop.
Movement Blur Blur created by using a slow shutter speed.