Stop watching 60s and HTF is pretty difficult, with too much room for error. The method I use is taking the video into an app, which you can add start and stop markers, then get the true times computed for you. Just using my phone and taking a video of your video, then using the app, I got 4.038 and 3.961. Still very fast... The app I use is VStopwatch
3.75 on bunt.