Diffraction SBIG STC-7, Руководство пользователя

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SBIG STC-7 CAMERA
USER’S MANUAL
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The sensor is mounted to the TE cooler, which in turn, is mounted to a heat
sink, usually the camera head housing. A TE cooler is also often referred to as
a Peltier cooler.
TIFF Image File Format - The TIFF image file format (which stands for Tagged
Interchange File Format) was developed jointly by Microsoft and Aldus
Corporations to allow easy interchange of graphics images between programs
in areas such as presentation and desktop publishing. MaxIm LT can save and
read image files in this format.
Transparency – Transparency in the astronomical sense refers to the total
transparency of the atmosphere from the ground to the edge of space. It is
largely dependent on the amount of water vapor in the air, but not entirely
analogous to the amount of the cloud cover present in a location. There can be
isolated clouds in a finely transparent air mass, and conversely, poor
transparency can occur when there is little or no cloud present. Man-made
light pollution and aerosols (i.e. industrial pollutants, volcanic ash, pollen, sea
salt, and forest fire smoke) also degrade transparency.
Refer also to “Seeing”.
Tri-Color - Tri-Color refers to color images created using three different colors
mixed into a balanced color image using red, green and blue filters. An object
is imaged three times, once with each color filter. The three images are then
co-added and color balanced using appropriate software, such as MaxIm LT.
Vignetting - Vignetting is the obstruction of portions of the incoming light
path by parts of an optical system. It usually occurs in the off-axis portions of
the image and is seen as an uneven illumination of the image plane. When
imaging using a vignetted optical system, the corners of the camera sensor will
receive less light. This can be compensated for by using flat-fielding
calibration, but it is usually preferable to physically avoid vignetting if possible.