<div dir="ltr"><div class="gmail-gs" style="margin:0px;padding:0px 0px 20px;width:1104px;font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium"><div class="gmail-"><div id="gmail-:w8" class="gmail-ii gmail-gt" style="font-size:0.875rem;direction:ltr;margin:8px 0px 0px;padding:0px"><div id="gmail-:w7" class="gmail-a3s gmail-aXjCH" style="overflow:hidden;font-variant-numeric:normal;font-variant-east-asian:normal;font-stretch:normal;font-size:small;line-height:1.5;font-family:Arial,Helvetica,sans-serif"><div dir="ltr"><h1 style="font-size:1.4em;margin:0.5em 0px;line-height:1.25em;color:rgb(0,0,0);font-family:arial,helvetica,clean,sans-serif"><p class="MsoNormal" style="margin:0in 0in 8pt;line-height:15.6933px;font-size:11pt;font-family:Calibri,sans-serif">Hi, </p><p class="MsoNormal" style="margin:0in 0in 8pt;line-height:15.6933px;font-size:11pt;font-family:Calibri,sans-serif">I Use a spiral model for CT  (Fan Beam) imaging; how can I reconstruct the output images with RTK?</p><p class="MsoNormal" style="margin:0in 0in 8pt;line-height:15.6933px;font-size:11pt;font-family:Calibri,sans-serif"><span style="color:rgb(34,34,34);font-family:Arial,Helvetica,sans-serif;font-size:small;font-weight:400">Do I Need Registration and Matching Projection Before iterative Algorithms(conjugate gradient, ...) Run?</span>  <br></p><p class="MsoNormal" style="margin:0in 0in 8pt;line-height:15.6933px;font-size:11pt;font-family:Calibri,sans-serif">Tank you.</p><p class="MsoNormal" style="margin:0in 0in 8pt;line-height:15.6933px;font-size:11pt;font-family:Calibri,sans-serif"><br></p><div><img src="cid:ii_k54vf7rq1" alt="spiral-ct-scanner.png" width="240" height="210" class="gmail-CToWUd"><br></div></h1></div><div class="gmail-yj6qo"></div><div class="gmail-adL"></div></div></div><div class="gmail-hi" style="border-bottom-left-radius:1px;border-bottom-right-radius:1px;padding:0px;width:auto;background:rgb(242,242,242);margin:0px"></div></div></div><br class="gmail-Apple-interchange-newline"></div>