Zeiss LSM 880, Operating Manual

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CHAPTER 1 - SYSTEM OPERATION
ZEISS Left Tool Area and Hardware Control Tools LSM 880
334 000000-2071-464 10/2014 V_01
The
Peak intensity to noise
filter defines the threshold of the signal strength of an identified peak over
background, at which the peak is regarded to be genuine. The filter works as follows:
−
The highest intensity peak with the intensity I is identified in the frame
−
The mean intensity M and the standard deviation SD is calculated from the frame
−
The Peak intensity to noise (PI) is set.
−
If I – M > SD x PI than the peak is regarded to be genuine
−
The peak is cut out of the frame and the next highest intensity peak is selected.
−
The procedure is repeated until I – M < SD x PI. Than the peak finding process will end for that
frame.
All identified peaks above the threshold will be displayed per frame in the Preview window (Fig. 451).
The higher the
Peak intensity to noise
factor, the more stringent is the peak selection. Too
low numbers will result in noise being falsely identified as peaks; too high numbers will miss
some genuine peaks. The preview can be taken to decide what the best value will be for the
particular image series. The default value of 6 will work in > 95 % of the cases.
Fig. 451 Preview window of the image container for PALM processing with the Peak
intensity to noise set to 3 (left), 6 (middle) and 10 (right)