I'm trying to record and playback (without blur) a golf club impacting a golf ball. When I try to go frame by frame its literally only 3 frames long and I'm using a 260FPS camera. It seems like a simple task, but I cannot get more than a few frames and its all blur.
- joan
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> Why is replacement frame rate maxed at 100fps?
The point of this feature is to create a file with a traditional (low) framerate inside it, so it can still be played back normally (although at slower speed than real time). So starting with a high speed camera but saving files with normal speed frame rate and video in slow motion (typical operating mode of a high speed camera). To disable this feature you can set the "Threshold" field higher than your actual capture frame rate so it will never trigger. Maybe there should be an explicit check box to make things clearer.
The limited number of frames in the output video and the blur seems to be two other separate problems. Blur is caused by too high exposure time. What camera model are you using?
Try to use the recording mode "Retroactive" for best performance if you are capturing short clips that fit in the delay buffer.
Thanks for the response, this is a link to the cameras I’m using.
ELP 260fps USB Camera for... https://www.amazon.com/dp/B0CXDTNS22
As far as the “threshold” there are only 3 places to manually input frame rates in the preferences. I’m not sure what you mean by retroactive in regards to shutter speed and or exposure. Thanks again
- joan
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The threshold setting is just above the replacement frame rate, in Preferences > Capture > Recording.
I don't think it's related to the problem, it only changes a metadata entry in the output file. The file will contain the same frames.
Retroactive is a recording mode, it's on the same preference page as replacement frame rate. It will record the video to the memory buffer, and only at the end of the recording will generate the output file on disk. The other methods write to the disk on the fly which can be slower (but can be used continuously for longer). See more details here: https://www.kinovea.org/help/en/userint … #recording
Exposure time is in the individual camera configuration dialog (from the wrench button in the lower left of the capture screen). Make sure it's lower than 4 milliseconds if you target 250 fps. https://www.kinovea.org/help/en/capture … ebcam.html