Region Of Interest - Princeton Instruments ProEM+ EMCCD User Manual

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Region of Interest

A Region of Interest (ROI) may be the entire CCD array or it may be a rectangular
subregion of the array. In WinX, the definition of such a region is done either from the
Easy Bin dialog accessed from the Acquisition menu or from the ROI Setup tab,
accessible after selecting Experiment Setup from the Acquisition menu. Easy Bin is a
simple way of a defining a single full chip width ROI. ROI Setup allows you to create
ROIs with greater flexibility in ROI location and width. In LightField, ROIs are set up
via the Region of Interest expander.
Each ROI is defined in the X and Y direction by a start pixel, an end pixel, and a
group/height (binning) factor. After one or more regions have been defined and stored,
data acquisition will use these regions to determine which information will be read out
and displayed and which information will be discarded.
In WinX, when ROIs are used to acquire data, the ROI parameter information (for the
first 10 ROIs) is stored in the data file when that data are saved to disk. You can review
this information for the active data display by using the File Information functionality
(accessible from the File menu or from the Display Context menu).
In LightField, when ROIs are used to acquire data, the ROI parameter information for
ALL of the ROIs is stored in the data file when the data are saved to disk. You can
review this information for the active data display by using the Show File Information
functionality (accessible from the Data Options menu in the Comparison Viewer).
Notes:
1. For Flatfield Correction, Background Subtraction, etc., the images must be exactly
the same size.
2. References to X and Y axes assume that the shift register is parallel to the X-axis and
that the data are shifted to the shift register in the Y direction.
When setting up a partial frame ROI in WinX, keep in mind that for the ProEM+ the
following constraint applies: the number of pixels in the serial (horizontal) direction
must evenly divisible by 4, even after binning. The software may refer to the horizontal
as X or Wavelength depending on the application. This constraint does not apply in
LightField.
Examples: These WinX examples include partial frame ROIs with and without binning.
The terminology is based on the WinX Experiment Setup|ROI Setup tab.
X Start to End = 200 pixels, no grouping (binning). Since 200/4=50, this is a valid
X Start to End = 200 pixels and grouping (binning) is by 8. The resulting number of
X Start to End = 240 pixels, no grouping (binning). Since 240/4=60 this is a valid
X Start to End = 240 pixels and grouping (binning) is by 3. The resulting number of
X Start to End = 240 pixels and grouping (binning) is by 16. The resulting number
ProEM
ROI setup.
super pixels is 25. Since 25/4=6.25, this is not a valid ROI setting for the
horizontal direction in WinX. However, this setting would be valid in LightField.
ROI setup.
super pixels is 80. Since 80/4=20, this is a valid ROI setup.
of super pixels is 15. Since 15/4=3.75, this is not a valid ROI setting for the
horizontal direction in WinX. However, this setting would be valid in LightField.
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+ System Manual Version 1.B