Hello,
I have a question regarding the calibration process when using camera tracking systems such as Mo-Sys and RedSpy.
Our studio has both an LED wall and an LED floor, and we plan to extend the virtual environment beyond the physical LED volume. When we purchased our Mo-Sys tracker, we received lens calibration data specifically matched to our camera body and lens. In Aximmetry, we enabled the External Lens Data option and used that calibration data.
In addition, we performed Tracking Calibration using the Aximmetry Calibrator. However, when moving the camera on a jib, we noticed that the extended area outside the LED volume did not align correctly with the content displayed on the LED wall. In other words, the virtual extension and the LED content gradually became misaligned as the camera moved.
To troubleshoot this, we recalibrated both the Lens Calibration and Tracking Calibration using the Aximmetry Calibrator, but the issue still persists.
At this point, we're not sure what the root cause is. Are there any common mistakes or important points to pay attention to during the calibration process? We've followed the documentation as closely as possible, but unfortunately haven't been able to resolve the problem, which is why I'm posting here on the forum.
Additionally, we're having trouble with LUT Calibration. We repeatedly encounter errors during the calibration process, so we're unable to complete it successfully. If anyone could explain the proper workflow or provide guidance on the correct setup and usage of LUT Calibration, it would be greatly appreciated.
Thank you in advance for your help.
Hi dnwndhfhfk,
First of all, make sure the lens file you received is loaded into your Mo-Sys tracker; from there it will be applied to the tracking data in Aximmetry once External Lens Data is enabled, which you said you have already done. Leave the Calibration Profile empty as well, and do not assign a Zoom Device — this ensures the camera uses the Mo-Sys lens data.
Then, set up the Mo-Sys tracker by doing the tracking calibration in Mo-Sys's system. If you run into trouble during this process, according to our latest knowledge, Mo-Sys offers calibration services for their products, so it may be worth contacting them for assistance.
Once done, test the tracking. You can use the following compound from the installed Projects root library for testing: Tutorials\AR\AR_Example.xcomp.
You can learn about the process of these tests in the following document:
https://aximmetry.com/learn/virtual-production-workflow/tracking/testing-of-the-calibration/testing-of-the-calibration/
If you experience issues with the tracking (the virtual overlay doesn’t move together with the camera), try calibrating the tracking again with Mo-Sys.
Should the tracking misalignment persist after all of this, try Free-D for tracking instead of Mo-Sys. Disable any calibration or lens file in your Mo-Sys system, then set up a Free-D tracking system in Aximmetry as described in our documentation:
https://aximmetry.com/learn/virtual-production-workflow/tracking/setting-up-specific-tracking-systems/setting-up-free-d-systems/
This way it’s guaranteed that Aximmetry receives the raw tracking and lens data.
With Free-D in place, continue with the Lens and Tracking Calibration in our Camera Calibrator. Its documentation also includes tips for achieving a better calibration:
https://aximmetry.com/learn/virtual-production-workflow/tracking/calibration/camera-calibrator/#calibration-tips
Test the calibration now. If you experience problems with the calibration made with Aximmetry Camera Calibrator, feel free to contact us at: sales@aximmetry.com, as we offer calibration services.
If you find the tracking fine, the next thing to check is the LED wall setup. The basic parameters of the LED wall(s), such as size and resolution, have to be set up correctly:
https://aximmetry.com/learn/virtual-production-workflow/led-wall-production/setting-up-the-led-walls/setting-up-the-led-walls/
If these values are off, the Digital Extension and the content shown on the LED wall will not line up. Aximmetry's Auto Place feature, which fits the physical and virtual LED walls together, is described here:
https://aximmetry.com/learn/virtual-production-workflow/led-wall-production/setting-up-the-led-walls/fitting-of-the-virtual-and-physical-led-walls/
The delays are the other crucial part of the setup, since they cause temporary misalignment between the extension and the LED wall while the camera is moving. For LED wall productions, we highly recommend genlocking every device in the setup: this way all devices use the same system clock, which reduces the chance of temporal misalignment:
https://aximmetry.com/learn/virtual-production-workflow/led-wall-production/introduction-to-led-wall-production/#genlocking
To sync the Digital Extension with the tracked camera's movement, adjust the Picture Delay CAM X value on the SELECT CAMERA control panel (CAMERAS control board), or use the Detect Picture Delay function for an automatic setup. You can learn more about this in the following document:
https://aximmetry.com/learn/virtual-production-workflow/led-wall-production/finalization/delays/
The tracking data needs its own delay setting as well, which this document explains:
https://aximmetry.com/learn/virtual-production-workflow/led-wall-production/setting-up-the-inputs/tracked-camera-inputs/#delays
As for the LUT calibration, could you tell us which version of Aximmetry you are running? LUT Measure has been improved over the last few releases, most recently in 2026.3.0, so the issue you hit may already be fixed in a newer version; see the version history:
It would also help to know the exact error message Aximmetry shows when the LUT Measure fails, as there are many possible causes. If the camera image itself looks fine — the LED wall fills it completely, it is not burnt out, there are no reflections — then one possibility is that your computer is overloaded, for instance by running Unreal and Aximmetry at the same time. In that case the LUT Measure sequence cannot run fast enough and the process halts.https://aximmetry.com/learn/virtual-production-workflow/which-aximmetry-is-right-for-you/software-version-history/
Warmest regards,
Adam