iQue Forecyt® Reference Guide (Version 9.0)

Analysis Mode Settings (Biexponential Scale Settings)

Analysis Mode Settings provides a mechanism for fine-tuning specific aspects of your data. When you click on the icon, this screen opens:

The Analysis Mode is set to biexponential by default (Automatic). Biexponential view is particularly useful when looking at compensated data that contains a significant number of events with negative fluorescence values. In certain assays, the spectrum overlap requires FCS data to be overcompensated, which results in populations shifting near or even below zero. Additionally, the instrument may produce events with negative values due to the subtraction of background fluorescence. Exponential scaling allows you to simultaneously see data near the axis as you would with linear scaling while also seeing the full extent of the data as with with log scaling. You also have the option to adjust the linear range of the biexponential to better display the events around the axis.

If you click Manual Override you can set a specific value for the Linear Range associated with a parameter. When you click Manual Override the Biexponential Scale Settings window opens (1). Clicking on a value (in the following example, BL3-H) enables the Set Values button (2). This in turn opens a dialogue box with drop-down menus for Calculate using Population and Use Value (3). In the following example we set it to Normal Singlets and changed the Value slightly (4). The new Linear Range table reflects the new setting and the Auto setting (6).