Allied Guppy, Техническое руководство, Страница: 228 / 238

Glossary
GUPPY Technical Manual V4.0.1
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Quantum efficiency Quantum efficiency (abbr. QE) is the measure of the effectiveness of an
imager to produce electronic charge from incident photons. Especially
important to perform low-light-level imaging.
RAW RAW is a file option available on some digital cameras. It usually uses a
lossless compression and produces file sizes much smaller than the TIFF
format. Unfortunately, the RAW format is not standard among all camera
manufacturers and some graphic programs and image editors may not
accept the RAW format. The better graphic editors can read some manufac-
turer's RAW formats, and some (mostly higher-end) digital cameras also
support saving images in the TIFF format directly. There are also separate
tools available for converting digital camera raw image format files into
other formats.
Readout Readout refers to how data is transferred from the CCD or CMOS sensor to
the host computer. Readout rate is an important specification for high-res-
olution digital cameras. Higher readout rates mean that more images can
be captured in a given length of time.
RGB The RGB color model utilizes the additive model in which red, green, and
blue light are combined in various ways to create other colors. The very
idea for the model itself and the abbreviation
RGB come from the three pri-
mary colors in additive light models.
Note that the RGB color model itself does not define what exactly is meant
by
red , green and blue , so that the same RGB values can describe notice-
ably different colors on different devices employing this color model. While
they share a common color model, their actual color spaces can vary con-
siderably.
Rolling shutter Some CMOS sensors operate in rolling shutter mode only so that the rows
start, and stop, exposing at different times. This type of shutter is not suit-
able for moving subjects except when using flash lighting because this
time difference causes the image to smear. (see global shutter)
RS-232 RS-232 is a long-established standard that describes the physical interface
and protocol for low-speed serial data communication between devices.
This is the interface that e.g. a computer uses to talk to and exchange data
with a digital camera.