Include Sources that are at least

This field sets the threshold value for including objects in sources that are detected. The value you enter or select from the list is combined with the choice of Sigma's or Counts to set the threshold above background.

Use Cursor ROI

Check this box to detect only those sources inside a rectangular region of interest defined by the image cursor.

Max Objects

Enter into this field the maximum number of objects that can be detected. This value is commonly used as a safeguard to prevent runaway detection of noise if you set the threshold too low.