Fixed Tag pose (viewed in fixed frame) changes when viewing from different angles

[jasmeet0915]

I am using the apriltag ros package with realsense d435 camera to determine pose of a tag for the purpose of docking. However, the pose of the marker changes depending on where in the image the tag is present. I have done multiple experiments with the same setup by keeping the marker at different heights and distances from the robot and have observed the deviation to be upto 30mm in most cases. I also tried using the infrared rectified image from the camera which produces the same results. I have also observed the tf jittering in most cases. Both the issues can be observed in the video below.

https://github.com/user-attachments/assets/5c814558-5b3f-4a22-aeeb-6336ffc9390c

Is this the expected performance? If not, what might be the issue here?