Hello,

Calibration needs a lot of patience and trial and error. 

The sensor size parameter is really important. You can look for the size of your camera sensor online.

The markers are there to give you an idea of how good your calibration is.

Thanks for your reply.

Yes, the sensor size parameter is import, I modify the parameter in UE aximmetry blueprint.

At Calibrating the tracker position chapter, it requires correct the Delta Head Trans, I wanna know how to judege if my parameter is correct enough?

Thanks.

Hi Beship,

Which parameter do you modify in the UE aximmetry blueprint?

Ahmed was referring to the sensor size in the Aximmetry Camera Calibrator. But you are probably not using the Aximmetry Camera Calibrator.

For the Delta Head Transf parameters, we suggest that you measure the distances (Pos x,y,z) in the real world and apply those. Note the distance is the offset between your tracker and where your camera's sensor is. The rotation values are more tricky as it is very hard to measure those accurately in the real world, so you will probably want to experiment with them in the virtual world. Or make sure that your tracker is precisely aligned.

Warmest regards,

Thanks for your reply.

I use Vanishing Point CalibrateX to get the lens distort vanishing json file:

I modify the sensor size in UE,  the camera parameter in Aximmetry_TrackedCam_3-Bill blueprint, filmback Sensor:

For the Delta Head Transf parameters, I did measure the distance. the rotation values are really tricky to measure.

My final result still dirft.

Hi,

The Sensor values in the Aximmetry_TrackedCam_3-Bill blueprint won't affect the tracking and you should probably not modify them.
You can set sensor size for tracking if you use the Aximmetry Camera Calibrator: https://aximmetry.com/learn/tutorials/for-studio-operators/basic-lens-calibration-without-lens-distortion/

The vanishing json file looks good. However, you could check if you can get better results using the manual zoom as it is described here:
https://aximmetry.com/learn/tutorials/for-aximmetry-de-users/experimenting-with-htc-vive-camera-tracking-using-unreal-scene/#calibrating-the-camera-zoom

Also, from your video, I get the impression that the height of the tracking data is not correct. Make sure that you correctly calibrated the Vive in SteamVR. And that the Cur position shown at Aximmetry - Edit->Manage Devices is the same as the tracker's position in the real world:

Warmest regards,

Thanks for your reply.

- Does the Aximmetry Camera Calibrator  available in Broadcast Edition? I'm using the Studio DE. Without the Camera Calibrator, is three any way to modify the sensor size?

- I use the manul zoom at the beginning, but get a drifting result, so I turn to use the Calebrate-X to get vanishing json file.

- I did calibrated the Vive in Steam VR refer to the Richard Frandzen video(https://www.youtube.com/watch?v=C8MZ7g0Czrc)

Hi,

Aximmetry Camera Calibrator is only available in Broadcast Edition. There is no way to modify the sensor size without it.
But, HTC Vive is not precise enough that the sensor size would change much on the precision.

By calibrating Vive I mean running the Room Setup:

And then making sure that the "Cur position" at Aximmetry - Edit->Manage Devices->OpenVR represent the real-world position of the tracker.

Warmest regards,

May I add please,

I use Vİve controller to track.

Room setup: I choose standing.

I have no HMD so using NULL.

My vive controller is placed on top of my camera at height 160cm

As setup asks me where is my tracker located I type in 160 cm as it is around that height.

Is this Calibration flow correct.?

Addition to this:

Which Compound I need to use in my scene What is the difference between

TrackedCam_Prev_3-Cam_3-Bill    AND   TrackedCam_Unreal_Prev_3-Cam_3-Bill

which of them I should add to my ue scene as a compound

Hello,

The TrackedCam_Prev_3-Cam_3-Bill uses Aximmetrty's own engine to render the scene.

While the TrackedCam_Unreal_Prev_3-Cam_3-Bill uses Unreal Engine to render the scene.

The choice is based on whether your scene is made using our engine or Unreal Engine.

Thank you Ahmad, but then There is Cam Transform pin is missing.. And I believe that I need that pin to track my camera in the scene No..?

If the scene is built by UnrealEngine For Aximmetry then I shall use TrackedCam_Prev_3-Cam_3-Bill

If the scene is built in Regular UE then I need to choose TrackedCam_Unreal_Prev_3-Cam_3-Bill  is that so.?

Hi Sinemaya,

Aximmetry doesn't work with Regular UE. You need to cook everything with UnrealEngine For Aximmetry.
However, Aximmetry has its own in-house render engine. This render engine uses the TrackedCam_Prev_3-Cam_3-Bill.
And UnrealEngine For Aximmetry uses the TrackedCam_Unreal_Prev_3-Cam_3-Bill.

You can add 3D objects and other 3D rendered objects for Aximmetry's own render engine inside Aximmetry Composer's Flow Editor.
TrackedCam_Prev_3-Cam_3-Bill inside Aximmetry's News Room example project:

TrackedCam_Unreal_Prev_3-Cam_3-Bill with an Unreal Project:

Warmest regards,