Q Imaging Retiga 3000, Руководство пользователя

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Retiga 3000 USER MANUAL
Gain State 2 uses the full dynamic range of the camera and is recommended for bright field applications. Gain
State 3, although only using a third of the single pixel full well, is ideal for resolving low luminescence signals.
Therefore, Gain State 3 is recommended for fluorescence applications.
Sensor Cooling
To reduce thermally generated noise attributable to dark current,
the Retiga 3000 camera system provides stabilized sensor cooling
of 0°C at up to a 30°C ambient room temperature. Additional
temperature control is available to allow flexibility in reaching
different stabilized sensor temperatures for various ambient room
conditions. The sensor temperature is set via software.
Additionally, the Retiga 3000 has the option of disabling its internal
fan for vibration-free and/or electrically sensitive applications. The
camera’s fan can be turned off by setting the temperature to +5°C.
Clocking Mode
The Retiga 3000 camera has two CCD clocking modes, one of which allows removal of the glow that can
appear in an image’s corners at longer exposures (arising from preamplifiers). In the PVCAM implementation,
the clocking modes are referred to as “Normal” and “Alternate Normal.”
In “Normal” mode, the CCD is optimized for precise exposure time control and maximum frame rate.
In “Alternate Normal” mode, the preamplifier is switched off during the exposure to eliminate the background
generated by preamplifier glow. However, switching the preamplifier off and on again adds additional time to
each exposure, especially noticeable when in Overlap mode (defined below). Since the actual exposure time
is slightly longer than the entered exposure time, Alternate Normal mode will increase the image brightness
due to the increase in light collected by the slightly longer exposure, as well as slightly decreasing frame rate.
As a result, it is usually beneficial to operate the camera in Alternate Normal mode for long exposures (>1 sec,
where preamplifier glow begins to be noticeable), and in Normal mode for short exposures (<1 sec, where
frame rate and precise exposure time are more critical).