Princeton Instruments PhotonMAX System, Manual, Page: 46 / 98

46 PhotonMAX System Manual Version 1.B
Note:
Since the first pixel to be read out from the Normal port is at the bottom
right (closest to the Normal port), the resulting image is a mirror image of the
same image if it were read out of the Multiplication Gain port. Some software
packages do a "horizontal-flip" in the software when the Normal port is selected
to ensure the correct orientation for all ports. In WinView and WinSpec, you can
specify a horizontal-flip on the
Hardware Setup|Display
tab page.
Controller Gain
Controller gain (a function of the preamplifier
and analog electronics) is software-selectable
and is used to change the relationship between
the number of electrons acquired on the CCD
and the Analog-to-Digital Units (ADUs or
counts) generated. In WinView and WinSpec,
gain selection is made on the
Acquisition|Experiment Setup…|ADC
tab
page (Figure 30). The choices are 1 (Low) , 2
(Medium) , and 3 (High) . Users who measure
high-level signals may wish to select Low to
allow digitization of larger signals. Medium is
suitable for experiments within the mid-level
intensity range. Users who consistently
measure low-level signals may wish to select
High , which requires fewer electrons to
generate an ADU and reduces some sources of
noise.
The "Certificate of Performance" supplied with
the camera lists the measured gain values at all
settings.
Figure 30. Selecting the Controller Gain
(Experiment Setup|ADC tab page)
Readout Amplifier
(Port)
Readout Rates
Controller Gain
(e
-
/ADU)
Multiplication Gain 5 MHz
10 MHz
#1: 12e
-
/ADU
#2: 6e
-
/ADU
#3: 3e
-
/ADU
Normal 1 MHz
5 MHz
#1: 4e
-
/ADU
#2: 2e
-
/ADU
#3: 1e
-
/ADU
Table 2. Typical Controller Gains