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The baselining procedure tries to eliminate backgound noise (Fig. 1).
The baselining process reduces each data point in the data by the local minimum value. The 'baselining width' defines the number of data positions that are to be considered for searching the local minimum (+ the central data point). The value at the actual data point position is set to its original value minus the minimum value.

For example, a baselining width of 20 lets the algorithm search for the smallest Y-value out of the actual data point position, 10 data points to the left and 10 data points to the right of the actual data point position.

The influence of different baselining widhts to the original trace data (Fig. 1) is shown in Figs. 2-6.

Tab. 1.
If the baselining width value is too large ...
... the background will not be eliminated efficiently because the minima found during the baselining process are not due to the base points of the local peaks.
As a result the peaks will remain on a background noise.
If the baselining width value is too small ...
... severe artifacts are generated!
If the baseline width is smaller than the width of a peak, the local minimum values in the center of a peak will be detected in the peak flank regions.
This leads to split peaks (see example with baselining width 10 and 20 below).

Tab. 2. Influence of the baselining width on the appearance of the final data.
Fig. 1. Smoothed raw data

The raw data has already been smoothed.

The peaks are sitting on a background as indicated in green color.
Fig. 2. Baselining width set to 10

Here the baselining width value is too low. This results in split peaks and drastic reduction of the peak heights.

Too low!
Fig. 3. Baselining width set to 20

Here the baselining width value is still too low. Both peaks are still split their height is too small.

Still too low!
Fig. 4. Baselining width set to 50

The entire background is removed. The peaks are not split and they sit on the baseline.

Fig. 5. Baselining width set to 100

No split peaks. Peaks sit on base line. Background removed.

Still good!
Fig. 6. Baselining width set to 500

The baselining width value is too great and, therefore, the peaks do not sit on the baseline.

Too great!