camera. If there are multiple cameras connected at once, adopting of
configuration file is not possible.
This is why SIPS camera drivers (and also camera drivers for other programs)
introduced enhanced naming convention of driver configuration file. Every Gx
series camera has unique identification number, stated on the camera shell (this
number is also displayed in the list of all connected cameras in the SIPS “CCD
Camera” tool). Camera driver tries to open configuration file, which name is
extended with the camera ID number. If for instance camera ID is 1234, driver
first tries to open configuration file named “g3ccd.1234.ini”. Only is such file
does not exists, general configuration file “g3ccd.ini” is used. So it is possible
to create separate configuration files describing filters in every connected
camera.
Cropping of the CCD area
G3 and G4 camera drivers are able to crop the image matrix even before the
image is passed to SIPS. Although it is possible to define sub-frames directly in
SIPS camera control tool, limiting camera resolution this way is not very
convenient when multiple frames of different types (light, dark, flat) are
acquired. If for instance the user wants to use only center area of a large CCD
because the optics used cannot utilize such large CCD detector, it is possible to
read only a sub-frame (sub-frame 512, 512, 3072, 3072 converts 16Mpx G4-
16000 camera into 9MPx camera). But different sub-frame is used e.g. when
focusing the camera and it is necessary to properly restore above mentioned
subframe before each dark, light of flat field is acquired. And 1 pixel difference
between light and dark frame harms the possibility to properly calibrate images.
This is why the 'g3ccd.dll' driver allows definition of sub frame in the
appropriate .ini file in the [crop] section:
[crop]
x = 512
y = 512
w = 3072
h = 3072
Such camera will report resolution 3072×3072 pixels to SIPS and all other sub-
frames, defined in the SIPS camera control tools, will be related to the above
defined subframe.
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