i am using photocells hooked up to the analogue input of a game controller which is being recognized as an hi device. i am trying to figure out a way to record when the amount of light being picked up is changing faster or slower, as in when the output of hi is changing faster i want i higher value, and a lower value when the output is changing more slowly. Basically i need a good way to track the rate of change of a signal. I have tried using the counter object and reseting at set intervals. I have also tried using the count function of the capture object. Neither of these have worked well enough. Any suggestions?