Vive tracker and lens calibration

FAQ Content Creation Virtual Camera Camera Tracking Unreal

 

Hi,

week ago we purchased some HMD, 4 base stations and bunch of vive trackers (latest iterations). Now I'm in middle of calibrating all of that, but I cant find any comprehend good walkthroughs or posts. I can calibrate trackers by following up Richards tutorial, after that I attached those to cameras, but I really cant tune any good position of billboards to scene to make it look reastically and right. Angles are wrong, when moving with camera it alls jitter and its just not well written process in documentation.

Can i somehow attach billboard (table) to a tracker and calibrate it with another tracker on camera? Or is that any good documentation that will include setting up of all trackers and how to precisely calibrate cameras?

Our equipment is some Blackmagic Studio 4K cameras (one with DZO Optics 10-24, and others with DZO Optics 20-70), Aximmetry Broadcast Edition, latest HTC Vive Pro 2, 2 controllers, 4 trackers, 4 base stations.

Thanks with regards,

David

   davidrynes

 
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TwentyStudios
6/21/2022 8:18:59 AM
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You will always have a hard time getting good results with Vive trackers. It’s just not a professional solution, despite what some people claim. The jitter is an hardware issue that can only be somewhat mitigated with filtering in Aximmetry.

 
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davidrynes
6/21/2022 8:53:10 AM
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Yeah I´ve read about those, but I´ve filter that and it looks alright. We have simple setup without any wild camera moves, only some simple crane pulls. Next step will be more professional solution. But my other questions still remains. Is there any comprehensive guide to lens calibration and how to have good perspective that will be same in virtual as in green screen studio?

 
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TwentyStudios
6/21/2022 9:16:34 AM
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Have you tried using the Advanced Camera Calibration app that comes with the Broadcast edition ?


Here is some basic info on camera tracking in Aximmetry as well:


https://aximmetry.com/learn/tutorials/for-aximmetry-de-users/using-tracked-cameras-and-augmented-reality-with-an-unreal-scene/

https://aximmetry.com/learn/tutorials/for-aximmetry-de-users/experimenting-with-htc-vive-camera-tracking-using-unreal-scene/


 
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davidrynes
6/23/2022 5:46:10 PM
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Hi @TwentyStudios, so we managed to calibrate lenses and create profiles, but we are still failing in calibrating origin point. I will describe you our process, so maybe you can help me.

  1. After booting up PC, I launch SteamVR, place HDM on floor and calibrate room.
  2. Then I launch aximmetry, open up project, put the Vive tracker in middle of our studio and set Origin point
  3. Then I will put tracker roughly one meter forward from origin point and set Forward point
  4. Lastly I will get back to Origin point and take the tracker one meter right from origin point and set Right point
  5. Then I will take tracker, mount it on the camera
  6. And everything is wrong. Studio transformation is messed up, plane in project is messed up. Nothing is calibrated. I've tried uprotated etc., and still nothing.

So is there any fault on our end in those steps?

Thanks!

 
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davidrynes
6/24/2022 9:35:41 AM
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UPDATE: We calibrate points with HDM on floor and now everythins is perfect!