First of all, thanks for the replies. What i did is set up the code such that the photosensor acts as a button press (when under a certain level). The code works 100% except when high speed (ie the speed of the dart) is introduced. Basically I need help getting the photosensor to detect the dart when at high speeds.
And yes i could technically just detect whenever the trigger is pressed but that could lead to miscounts (ie if you pull the trigger without a dart loaded etc.) plus it is more of a coding/hardware challenge and those are always fun.