1 Topic by mpnn

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I set up Kinovia with a webam and tried to record a timed event with the camera pointed at finish line.  I hit record when the gun went off to start the race.  I assumed that when I reviewed the video and used the stopwatch my time for a finisher would be very close to the actual when compared with a different fully automatic timing system.  Maybe only a couple of tenths difference.

However, my results were sometimes as much as 2.5 seconds different than a verified time using FAT on a 28 second race.  I tried doing this for a 2:30 minute race and was off more than 10 seconds. 

Is this a calibration issue?  Is there a delay from when I hit the record button and the actual recording?

If I push record at the start gun shouldn't the stopwatch match the actual time using a verifiable fully automatic time?

2 Reply by joan

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Hello,
This is an important known issue that is being worked on.
The problem boils down to not knowing the framerate of the video we are saving, because we don't receive frames at the same frequency when simply viewing compared to recording.
The discrepancy depends on the CPU load…

3 Reply by HDAV

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Having just tried the stop watch on 0.8.17 it seems to count frames rather than give a time time in seconds/minutes etc. Video is configured for camera 120 fps and playback is 15fps event lasts 18 frames so should be 0.15 seconds in real time?

4 Reply by joan

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I think the original post issue is specific to the capture screen and should be fixed in 0.8.16 forward.

Regarding the stopwatch, it will follow the configured "time format" from Options > Time markers format. Double check if you have it set to "classic" or "frame number". When using timed format, it should indeed take into account the time adjustment for high speed camera.

5 Reply by HDAV

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joan wrote:

I think the original post issue is specific to the capture screen and should be fixed in 0.8.16 forward.

Regarding the stopwatch, it will follow the configured "time format" from Options > Time markers format. Double check if you have it set to "classic" or "frame number". When using timed format, it should indeed take into account the time adjustment for high speed camera.

Great thanks big_smile