Inconsistent start line placement

Hi. Newbie

Just downloaded the free version to test, imported my go pro footage, lap times weren't starting on the start line so paused the video, skipped frame till I was bang on the start line and CTRL and click the 'set start / finish position' button, but then the next time I pass it starts the next lap time 10-20m before the start line?

I tried re setting it then for that lap but then rewind to the start of that lap and it starts the timer miles away from the start line again.

Using a Gopro Hero 5 and MacOS version of the software.

Thanks in advance.

I've found that the GoPro GPS can be relatively accurate, but if you're looking for something exact down to the frame, then you probably need an external GPS. If the times that RaceRender is calculating based on the GPS are many frames off, then the GPS may not have had good signal on the day it was recording.

If you have exact timings (e.g. provided by the track day organizers), then you could add these in. Alternatively, you could alter the ones calculated by RaceRender to be a bit more precise (which from the sound of your post is probably closer to what you're looking for). You can do this by clicking on the Input File for the data, and then clicking the Laps button (next to Create Video), then click Edit Lap Times, and add the times in the format:

Code:

---

Lap 000: 00:00:15.905
Lap 001: 00:01:01.262
Lap 002: 00:00:59.367
Lap 003: 00:00:59.289
Lap 004: 00:01:00.567

---

where "Lap 000" is the time between when the video starts and when you cross the line on your first lap, and all other laps are in Hours:Minutes:Seconds.Milliseconds and leaving off any time after the last lap until the end of the video. I would recommend finding exactly when you cross the start line each time and noting the time in the bottom right of the screen, and then just subtract each pair to get the "exact" lap times (plus or minus approximately one frame). That should give you a much more accurate lap timer.