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</o:shapelayout></xml><![endif]--></head><body lang=IT link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='mso-fareast-language:EN-US'>Hi Clément,<br><br>It seems likely that your geometry is not 180+fan-angle complete and therefore cannot lead to a proper reconstruction. From your attached geometry, you sweep from 0 to 178° (180-increment). <br><br>My suggestion would be to try some intermediate angles, so to recreate a complete ShortScan. I suggest you to try at least a 200/220 ° arc to check on your simulation pipeline.<br><br>I hope this is helpful,<br>Gabriele<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b>Da:</b> Rtk-users <rtk-users-bounces@public.kitware.com> <b>Per conto di </b>Clément Mirabel<br><b>Inviato:</b> venerdì 11 dicembre 2020 09:11<br><b>A:</b> rtk-users@public.kitware.com<br><b>Oggetto:</b> [Rtk-users] Trying to reconstruct with a 180 degrees circular projection geometry<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p><div><p style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:12.0pt;margin-left:0cm;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#24292E'>I have been trying to set the geometry in ThreeDCircularProjectionGeometry with values between 0 and 180 degrees, to reproduce the motion of some acquisition systems, but reconstruction is far from the expected result when the gantry angle does not reach max value of (360-increment). (Attached is the geometry file generated)<o:p></o:p></span></p><p style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:12.0pt;margin-left:0cm;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#24292E'>My workflow is the following :<o:p></o:p></span></p><ul type=disc><li class=MsoNormal style='color:#24292E;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif'>Apply JosephForwardProjectionImageFilter on a 3D Volume<o:p></o:p></span></li><li class=MsoNormal style='color:#24292E;margin-top:3.0pt;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif'>Try to reconstruct using FDKConeBeamReconstructionFilter<o:p></o:p></span></li></ul><p style='margin:0cm;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#24292E'>Although, the result from JosephForwardProjectionImageFilter describes a 180 degrees rotation, the output of the reconstruction seems to display rays from opposite direction but not from rotated directions<o:p></o:p></span></p><p style='margin:0cm;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#24292E'><o:p> </o:p></span></p><p style='margin:0cm;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#24292E'>Here is a view of what is supposed to be an axial slice:<o:p></o:p></span></p><p class=MsoNormal style='box-sizing:border-box'><img width=350 height=353 style='width:3.6458in;height:3.677in' id="Immagine_x0020_1" src="cid:image001.png@01D6CF9F.1AF87AD0"><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal>Thanks for your help!<o:p></o:p></p></div><div><p class=MsoNormal><span style='color:#888888'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='color:#888888'>Clément<o:p></o:p></span></p></div><p style='margin:0cm;box-sizing:border-box'><span style='font-size:10.5pt;font-family:"Segoe UI",sans-serif;color:#24292E'><o:p> </o:p></span></p></div></div></div></div></body></html>