Response latency measurement as precise as possible

Hi there,

I just started using PsychoPy and I’m developing an experiment with the Builder of PsychoPy. The time from upon the moment where a stimulus shows up, until the time where the right key is hitten by a person, is my response latency. To measure this as precise as possible, I wondered if it is necessary to count with frames instead of second durations; what are your previous experiences in measuring response latencies using PsychoPy / which variations did you get? In the order of 1, or 10 milliseconds?

Also, do you know where I can find the refresh rate of my mac? it doesn’t show up on the display preferences…

PS: The timebyframe demo showed that there are no dropouts over 500 frames run on my mac.