FBP with sinogram obtained by real equipment

[Naoki-Ikezawa]

I tried to reconstruct sinogram (obtained with real equipment) with torch-radon FBP method. But I only get first image. It may contain a very small object. The second image is obtained by another reconstruction method.

I used "torch_radon.RadonFanbeam()".
There are parameters.

resolution = 512
source_distance = 55 [mm]
det_distance = 148 [mm]
det_spacing = 0.276890625 [mm/pixel]

I wonder if we have to transform parameters when I apply torch-radon FBP for real data.
How can I solve this problem? Thanks.