Changing Calibration Settings

Post Reply
clindsay
Posts: 3
Joined: Mon Aug 22, 2016 5:13 pm

Changing Calibration Settings

Post by clindsay »

Hello,

Recently I acquired several takes with a calibration that had the wrong wand size selected. Is it possible to recalibrate using the same wand data and reconstruct the takes? Thanks.
steven.andrews
NaturalPoint Employee
NaturalPoint Employee
Posts: 737
Joined: Mon Jan 19, 2015 11:52 am

Re: Changing Calibration Settings

Post by steven.andrews »

Hello clindsay,

Thank you for reaching out to the community regarding this question.

It is possible to recalibrate using a recorded wand wave. In order to do this, you can follow the steps described in our online documentation.
http://wiki.optitrack.com/index.php?tit ... alibration

If you require any further assistance with this, please feel free to continue working with us through your open Support ticket, as that will be a faster method for communication than this forum.

Best regards,
Steven
--
Steven Andrews
OptiTrack | Senior Customer Support Engineer
clindsay
Posts: 3
Joined: Mon Aug 22, 2016 5:13 pm

Re: Changing Calibration Settings

Post by clindsay »

So no way to modify the existing calibration? It is not possible for me to collect anymore data from that session.

In other posts, it is mentioned that setting the wrong wand size is a common mistake and that the recorded data in the takes would be off by a scale factor. How would I determine this scale factor if I cannot modify the existing calibration? Is there a way to fix this with the API (i.e. write some code to convert the take data or edit the cal)?
steven.andrews
NaturalPoint Employee
NaturalPoint Employee
Posts: 737
Joined: Mon Jan 19, 2015 11:52 am

Re: Changing Calibration Settings

Post by steven.andrews »

Hi clindsay,

If you are using a current version of Motive, the Wand Wave and the Ground Plane takes are recorded automatically while you are calibrating. You would see these listed in the session that was active during calibration. In order to recalibrate, you would just need to load the wand wave, select the correct wand size, then perform the offline calibration as described in the provided steps.

The incorrect scale depends on your settings. If you set Motive to use a 500mm wand and then use a 250mm wand, your data will be twice the actual scale.

The API could most likely be used for this purpose, but it would be much easier to re-run the calibration, then to open the new calibration file in the incorrect takes. You could also just change the scale when exporting the file types you need, such as a CSV file.

Best,
Steven
--
Steven Andrews
OptiTrack | Senior Customer Support Engineer
Post Reply