[Rtk-users] More errors with 360 projections than 180 for SART

[anais.capouillez at student.uliege.be]

Hi,

I'm reconstructing a homogeneous cylinder. My problem is that I have better results for 180 projections, than for 360 for SART (with default parameters), and the same geometry (except the number of projections).

I don't understand why adding projections adds more errors, since it should be better (and for other algorithms this is indeed better with 360 projections).

With 180 projections, the mean error on the cylinder is 1,6% , and the maximal error is 21,6%. While, with 360 projections, on the cylinder the mean error is 6,4%, and the maximal error is 169%.
Even if I don't take into account voxels close to edges, there are more errors with 360 projections.

Is there a reason why I obtain worse results with 360 projections?

Since my files are too big, I added them here https://drive.google.com/drive/folders/1AYumjqNGUr8DZ0kxIbF7Ab1xet7srk-z?usp=sharing. I also added a file with the commands I used.


Thank you very much.

Anaïs