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Can someone either explain these parameters or point me to documentation that does?:

Lock Principle point
3rd order intrinsics
Solver Thread
Precision Cap
Interleave Groups

Also what is the difference between the version 1 and version 2 of the point cloud reconstruction engines?

Thanks,
Joe

Hey Joe. Here's some info:

Lock Principle Point: When you set this to True, you're essentially saying that the camera's lens is perfectly centered over the image sensor. The only reason to set this is if you have a camera arrangement that is very hard to calculate. This will lower the number of things the calibration algorithm is solving and hopefully allow the system to calibrate.

3rd Order Intrinsics: This enables a more complex model for the lens distortion but is likely to slow the calibration because it's solving something more complicated. If you want to try this option. Let the calibration run for a while. When it's essentially at the solution, you can enable this option and watch and see if the solution gets any better.

Solver Thread: You can adjust the priority of the solving thread. If running the calibration makes your computer nearly unusable you can dial this down a bit. Otherwise there is no need to adjust it.

Precision Cap: This limits the amount of data coming from USB cameras when in Precision Mode. This prevents potentially unstable situations that can arise when you walk in front of cameras and cause large spikes in data. There is typically no reason to adjust this setting.

Interleave Groups: If you have set of cameras running at the same speed in two different camera groups you could potentially delay the shutter group of one of the groups to half of the frame period. Then check this option on both groups to effectively double the sampling rate of the volume.

Regarding the point cloud engines. Point Cloud v2 is better than Point Cloud v1 =) Realistically you're not going to see much difference. However Point Cloud v2 is using an entirely new technique for point cloud reconstruction that should allow for higher marker counts and better performance. The output itself will be basically identical.

Thanks for the info Doug.

-Joe

Is there there any documentation on the point cloud settings and what they do? i.e. risudual, ray length, etc. We are constantly getting close facial markers jumping to each other and have found that tweaking some of these settings help but having a clue what they might adjust would help.

There is for Tracking Tools, it's in final review, and should be posted within a week or two once the review is completed. Check back to the OptiTrack site often to see if it's been posted. There will also be announcements posted here in the forums when it's officially released.

An Arena manual is in progress, and should be posted end of year or Q1 2012. If you are looking for the meanings of terms or Options in Arena, check the Tracking Tools manual once it's released as a reference, it should hold true.