Bio-Rad Firmware & Software Updates - Manual (Page 69)

Data Analysis Overview
58
Data Analysis Settings
The Amplification chart data in the Quantification tab shows the relative fluorescence (RFU)
for each well at every cycle. Each trace in the chart represents data from a single fluorophore
in one well. These data are used to determine C
q
values for each well on a per fluorophore
basis. The software uses one of two modes to determine C
q
values:
• Regression. This mode applies a multivariable, nonlinear regression model to individual
well traces and then uses this model to compute an optimal C
q
value
• Single Threshold. This mode uses a single threshold value to calculate the C
q
value
based on the threshold crossing point of individual fluorescence traces
Select Settings > Cq Determination Mode to choose the C
q
determination mode.
Adjusting the Threshold
In Single-Threshold mode, adjust the threshold for a fluorophore by clicking on the threshold
line in the Amplification chart and moving the mouse pointer vertically. Alternatively, specify an
exact crossing threshold for the selected fluorophore by following these instructions:
1. Select one fluorophore in the fluorophore selector in the Quantification tab (Figure 37)
by clicking the boxes next to the fluorophore name located under the Amplification chart.
2. Select Settings > Baseline Thresholds in the menu bar to open the Baseline Thresholds
window.
3. Adjust the crossing threshold (Figure 40) for the fluorophore by clicking User Defined
and entering a threshold number.
Figure 40. Baseline Thresholds window.
4. Click OK to confirm the change and close the window.
TIP: To have the same threshold value used for all of your data files define this in
the Data Analysis tab of the User Preferences window. This value will be applied
to all subsequently created data files.