User Guide

Glossary
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noise Effect produced when a variety of pixel colors are used in the same
color region. Noise often results during image resizing, or when
converting an image to a new format.
opacity Determines how visible an effect is when applied to an image or a
selection. High opacity produces a more solid effect, while low
opacity results in a nearly invisible effect.
overexposed Images that are overexposed have too many highlights, and tend to
look faded or grainy. You typically overexpose images by exposing
your digital camera's sensor to light for too long.
panning Moving zoomed images vertically, horizontally, and diagonally
across the display area to view specific areas of the image.
PDF An acronym for Portable Document Format. You can view PDFs on
any computer using the free Adobe Reader software.
perceptual Rendering intent that scales all of the colors within one gamut to fit
within another gamut. Best used for photographic images, as it
maintains the relationship between the colors more accurately than
the colors themselves.
perspective distortion Perspective distortion is caused by wide angle and telephoto
lenses, which distort the perspective of large or far-away objects.
For example, if you take a photo of a tall building, the building may
appear to be narrower at the top even though the building is the
same width from top to bottom.
photo album See album.
photo editor See image editor.
picture viewer See image viewer.
pincushion distortion In pincushion distortion the photo appears to shrink inwards
toward the center.
pixel (PICture ELement) Smallest visible portion of a digital image, arranged in rows and col-
umns.
plug-in Software module that adds functionality to a larger program.
PPI (pixels per inch) Measurement of how an image is displayed. More pixels per inch
result in higher image quality.