A system and method for measuring signals having a wide range of intensity components using detectors adapted for use in biological analysis devices. In certain biological analysis applications, signals emitted by a sample may have intensity components that vary over several orders of magnitude. Measurement of such a signal may yield an acceptable quality for one intensity component at the expense of another component. For example, a detector configured to measure a relatively weak intensity component may cause it to overflow when subjected to a relatively strong intensity component. The detector can be adapted to be operated at different configurations to allow measurements of different components of the signal, and the results can be combined to yield an accurate representation of the signal.