Hi,

You can correct this by setting the Delta Cam Transf parameter for each input's ORIGIN. More information on this can be found here: https://aximmetry.com/learn/virtual-production-workflow/tracking/advanced-information-and-features/camera-and-head-transformations/#origin-panels
The best approach is to use the Detect Origin feature to automatically align the origins.

The reason the green screen graphics in the STUDIO panel may appear aligned is likely because you set it at a depth that happens to look similar from all cameras.

Even after adjusting the Delta Cam Transf positions, your billboard might still look different in the virtual studio, as is in your screenshots, if the floor level in your virtual scene does not match the floor in your physical studio. To fix this, make sure the floor in your virtual studio in Unreal Editor is at 0 height (zero elevation). Additionally, when using the Detect Origin feature in Aximmetry, place the Aruco marker on the physical floor of your real-world studio. This will ensure the virtual and physical floors are in sync.

Regarding your question: "So this means that I can have my 1A billboard located at a certain point, and the 1B billboard located in a totally different scene, e.g., outdoors?"

You are referring to 1A and 1B billboards, which are both linked to the same INPUT (you can split one tracked camera video input into multiple billboards). The billboards of the same INPUT can be only separated as much as you can do it with the Billboard's Transformation parameter, which will result in separating them mostly in depth.
If you want to actually place the 1A and 2A billboards (Billboards of different INPUTs) in completely different scenes or areas, you can do this, even using the Delta Cam Transf parameter of the ORIGIN panel. However, it's recommended to use the Base Cam Transf parameter in the SCENE panel for this purpose. This will offset every camera to different locations.

If needed, you can set up logic in the Flow Editor to automatically change these values (for example, by pressing a button or when switching to a different camera). If you’d like, I can provide more details on how to set up such logic.

Warmest regards,

Hi Eifrat!

Thank you for your detailed reply.

Let me clarify a bit more what I meant by the setup I previously shared.

I positioned my 3 cameras as follows (see the image below):

1️⃣ Cam 1 is placed at (0, 0, 0).
2️⃣ Cam 2, which is 2 meters to the right of Cam 1, is placed at (2, 0, 0) in the Delta Cam Transform and is rotated 45°.
3️⃣ Cam 3, which is 2 meters to the right of Cam 1 and 2 meters up from Cam 2, is placed at (2, 2, 0) in the Delta Cam Transform and is rotated 90°.

This is why my green screen mask in STUDIO aligns perfectly with all 3 cameras.

Then i change the Delta Cam Transf of the SCENE node to position Cam 1 Where i want it in the Virtual Studio

So far, so good.

The problem occurs when I place the billboards.

If I simply put them directly in front of each camera at a certain distance (say 2.5 m away), they appear in a completely different position.

And if I try to adjust their positions by changing the Delta Cam Transform, it misaligns them with the STUDIO's mask.

That's where I'm stuck, because:

• Changing the scene's Delta Cam moves all cameras equally. ❌

• Adjusting the Delta Cam Transform of each camera misaligns it with the green screen. ❌

• Moving the billboards individually doesn't make sense, because if I have the actor positioned at the center of the studio, the billboard should align directly in a straight line with each camera. ❌

  
  

E.g

"If you want to place 1A and 2A billboards (billboards for different inputs) in completely different scenes or areas, you can do this — even by using the Delta Cam Transform of the ORIGIN panel. However, it's recommended to use the Base Cam Transform parameter in the SCENE panel for this purpose, as it offsets all cameras at once."

Yes — sorry for the confusion. I meant 1A and 2A, which are different inputs. Here the problem with using Delta Cam Transform remains the same: if I move, say, Cam 2 20 m away from Cam 1 (even though that's not physically true), it falls outside the range of the STUDIO mask.

I know I can use triggers to reposition the scene instead of the cameras when switching between inputs, but I was wondering if there’s a more “built-in” way to handle this.

Thanks again!

Hi,

To ensure the billboards are in the same position, they must have identical transformation values. The Lock To Camera feature is not suitable for your requirement because it only aligns the billboard to one camera at a time. Even if you try to use it, you would need different Locked Distance values for each camera. Also, it is probably more important to align the billboards relative to the table in your studio, rather than to the cameras.

For precise alignment, make sure each billboard shares the exact same Transformation values, and Lock To Camera, Auto Postion, and Look At Camera options are turned off:

I think, at first, you should really verify that your three PTZ cameras are accurately positioned in Aximmetry. In recent versions, you can display all camera positions within the virtual world. For example, if you point your PTZ CAM 1 at CAM 2, you should see a virtual representation of CAM 2 exactly over the video image of the PTZ camera in the studio view (if Show Cameras is enabled). Additionally, enabling options like Show Cam Heights, Show Cam Frustums, and Markers Visible can help you confirm the camera zoom and height settings, while seeing them in both the Studio and Scene views.

More about these settings here: https://aximmetry.com/learn/virtual-production-workflow/tracking/testing-of-the-calibration/additional-tools/#introduction 

Warmest regards,