''camera_angle_x'' seems to be wrong for several scenes

[LiuJF1226]

When I use colmap to process the synthetic scene chair, I find that the focal length is far away from that computed by camera_angle_x in transforms_train.json. Then I check the blender files for all 8 synthetic scenes. 5 scenes are correct while 3 scenes (chair, diningroom, sponza) are wrong.

1.chair: blender data is CAMERA_FOV = 33.8984° (0.5916387 in radian) while json data is camera_angle_x = 0.8575548529624939 in radian.
2.diningroom: blender data is CAMERA_FOV = 48.498° (0.8464498 in radian) while json data is camera_angle_x = 1.1884186267852783 in radian.
3.sponza: blender data is CAMERA_FOV = 22.8952° (0.39959663 in radian) while json data is camera_angle_x = 0.5897874236106873 in radian.

When using the blender data instead json data for the 3 scenes, I can obtain focal length close to the colmap results.