Large errors when using not integrated IMU

Hi @NikolausDemmel, I'm using Basalt with a stereo camera setup where the IMU is placed approximately 25 cm away from the cameras. Compared to a setup with an integrated IMU-camera system, I'm observing significantly higher pose estimation errors. Additionally, I noticed that the estimated trajectory becomes less smooth when using a more distant IMU.

I'm confident with the extrinsic and intrinsic calibration, even if I understand that in my case small error in the extrinsics would be amplified by the distance.

Beyond that, I was wondering if there is any assumption in the Basalt code that the IMU and cameras are physically close to each other. Could this assumption explain the degraded performance in my case? For example, I'm thinking about apparent motion or something related to optimization windows that maybe don't take into account the case of far away IMUs.