Hi Jim,

You could use the Delta Cam Transf to offset one of the input's tracking:

However, we suggest you use the tracking software/driver to align the two tracking solutions to the same position or orientation.

Also, it could help a lot if you can detail the situation in more detail. Which two tracking systems do you use, why do they have different orientations, and why it was not possible to set up them in a way to have the same origin (zero) point in the world.

Warmest regards,

I figured one could have a button or compound to align two different tracking systems when putting the tracker of system B and the same spot as system earlier. By remembering the value that A had. So that it gets more precise, since each tracking system got calibrated separately and may be ever so slightly off from each other.

Hi Eifert,

Is there a solution to do this type of alignment of two coordinate systems programmatically? I guess there could also be lens profiles active that have an impact.

Hi Jim,

I guess the only way is you put the first tracker to a fixed position in your studio and record its position. Then put the second tracker to the same fixed position and record its position. Then you just need to subtract the two positions from each other to get the offset between them.

You can easily save the data of the camera's transformation using the Capture Input option:

After you pressed Capture Input, you can disconnect the connection to the Copy Transformation, and the In input pin will have the transformation that you previously 'captured'.

Warmest regards,

When you use this cam transform is that the position of the tracker or does it incorporate potential offsets (for example from lens calibration on tracking system or lens calibration in Aximmetry in case that applies)? What if the camera offsets are different between trackers?

Hi Jim,

You can set in the Camera tracking to use the camera lens calibration profile or just leave it blank to not use it. It depends on your setup, but most likely you will want the calibration profile there and use that profile also in the camera compound's inputs.

By the way, you can even do this with camera compounds:

Warmest regards,

Some of Tracking systems have already calibration embedded so to clarify I am asking which value your camera transform actually is. 

For some trackers, is it the actual tracker position?

while for other tracking systems, it could be the position of the actual camera right?

so if we subtract those two camera transform values by putting the trackers in the same place, it would not give us the correct value? 

So how do we get the tracking transform without applying any camera offset calibrations? Is there a feature for that in Aximmetry?

Hi Jim,

Yes, some tracking systems send the Camera's final position, and in some tracking systems you can set up Delta Head Transf or Aximmetry camera calibration that will specify the camera's final position (by an offset from the tracker's position).
Depending on the tracking and your workflow, like working in multiple studios can change the workflow a lot. It can also vary when will you change such offsets and calibrations.

So it is hard to tell which state of your tracking you want to compare.
Like in the case of using the camera compound's Cam Transform output pin after specifying the Delta Head Transf or Aximmetry camera calibration, should work, if you do this every time you change the tracking location/calibration.

Warmest regards,

@Eifert,

our main tracking system has its own lens calibration and knows the camera offset.
Are you able to access the camera offset for the tracking system?

If we move a tracker without embedded camera calibration to the position of a tracker from tracking system with lens calibration like you were suggesting, then the values aren't lining up correct? We need to somehow get the raw tracking position from the tracking system that incorporates its own lens and camera offset calibration correct?

any suggestions? could this be automated with some nodes?

Hi Jim,

It is likely the tracking system will not send the calibration offset, only just the final position. If it does send it, you can try accessing it through the Native Transf pin:

Also, you might just want to change in the tracking system the offsets to 0, if that fits your workflow.

The Lens distrotation is also possible to access from the Camera Tracking module. So you can put these values together to achieve a similar result as camera compounds do with your manual set values.

Warmest regards,

So let's say tracker A has camera offset incorporated, while tracker B does not and Aximmetry handles the camera offset for tracker B.
To get two comparable tracker positions between tracking systems, we then would need to substract the camera offset used by tracker A first to try to go back to the original actual tracker A position. Tracker B does not use camera offsets so we assume the Aximmetry has the non-offset location as Aximmetry has to compute the offset for tracker B. Correct?
This assumes that we calibrate the two coordinate systems by putting tracker B exactly where tracker A is.
If you have any better suggestions here, let us know.

"The Lens distrotation is also possible to access from the Camera Tracking module. So you can put these values together to achieve a similar result as camera compounds do with your manual set values."
Do you mean if we get the lens data from Tracker A / tracking system with focus data, we could copy the data to also apply for tracker B in case we use the same lens later? Can you utilize a focus encoder position?

Hi Jim,

Yes, "Tracker B" will have a position without offset if you use it with a blank Camera Lens value:

You could use the lens data with other tracking systems and with the same camera if the lens distortion does not change over time. If it changes due to focus or zoom, I guess you can use it with the same focus and zoom levels.

Warmest regards,

Would be good to have a proper tool to align tracking systems as its one of the key value props (can support multiple Tracking systems vs. being tied to one).

The lens calibration in Aximmetry does not track focus unfortunately so its not really usable.

@Eifert - as a follow-up: is there any graphical way in Aximmetry to set the zero point for a tracking system? Sort of click on a certain 3D point in the Unreal scene and then it gets set to 0,0,0 right away. It's a bit odd to calibrate otherwise as one has to change the values with numbers and sliders, instead of saying: "oh ok for this scene, this is our origin point." Rotation is not as bad once you have the origin.

Hi Jim,

You won't be able to get a certain 3D point in the Unreal scene, as currently, you can only get video from Unreal into Aximmetry.
Alternatively, if you want to set up some kind of system like this, you will have to do it in a (dummy) scene rendered by Aximmetry. However, it might be easier to just copy-paste the position from Unreal to Aximmetry.

Warnest regards,

Was there any update to have a feature to align two tracking system coordinate systems?

Hi Jim,

We don't have a specific tool for this. But in the LED Wall compound, you can visualize now the cameras of two different tracking systems. This can greatly help you in verifying if the alignment is correct:

Warmest regards,

@Eifert - very cool. Is there a way to get this added for the 8 mixed tracked camera compound too?

Hi Jim,

There is no easy way to add this to the other tracked camera compounds.

However, we have on our list to make tracked compounds have more or better studio helper graphics.

Warmest regards,