This article describes why the Intel® RealSense™ Depth Camera D415 is better suited for longer distances than the D435 camera.
I would like to know the maximum distance at which the Intel® RealSense™ D400 Series cameras can detect objects and which camera is more suitable for longer distances.
Normally, the depth sensor from the Intel® RealSense™ D400 Series cameras is set to generate depth for objects at distances ranging from minZ-to-infinity. MinZ represents the minimum distance at which the camera can detect depth (refers to the Z coordinate).
At longer range, the depth accuracy will drift noticeably after 3 to 4 meters away from the camera. This is called RMS Error.
This link has a chart that shows RMS (Root Mean Square) error over distance for Intel® RealSense™ Depth Camera D415 and D435. The Intel® RealSense™ Depth Camera D415 camera is better suited for scanning objects at longer distances.
Please review the Best-Known-Methods for Tuning Intel® RealSense™ D400 Depth Cameras for more guidance on how to increase depth accuracy.