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    Hi MG,<br>
    Sorry, I realized I said something stupid. Using tif or mha won't
    make any difference because there is a branching on the pixel type
    in the <a
      href="http://www.openrtk.org/Doxygen/classrtk_1_1ProjectionsReader.html">projectionsreader</a>
    (search for ushort in the graph of the <a
      href="http://www.openrtk.org/Doxygen/classrtk_1_1ProjectionsReader.html">doxygen
      doc</a>) and unsigned short are handled differently. <br>
    The enclosed pyhon code will reproduce the same as my previous
    command line application. The commented code in it is what I
    initially used to read projections without any processing, i.e.,
    assuming line integrals.<br>
    I still think there is a problem in the geometry but someone (you?)
    has to spend sometime trying to understand what are the parameters
    from the Matlab code.<br>
    Keep us posted and good luck,<br>
    Simon<br>
    <br>
    <div class="moz-cite-prefix">On 28/01/2016 22:27, MG Vallet wrote:<br>
    </div>
    <blockquote
cite="mid:CACy6zzLBB-gTfc_ec6eML=kriSeGfMj2dPbjMGGBigWKfkegeg@mail.gmail.com"
      type="cite">
      <div dir="ltr">Louie,
        <div>I played with sdd and sid, following your advise. But they
          have few effect, clearly less effect than proj_iso_x. And none
          of these parameters can significantly improve my result. </div>
        <div><br>
        </div>
        <div>Simon,</div>
        <div>I carefully checked every input data and I cant see what I
          did wrong. I want first to reproduce your output. You said
          earlier it's easy to convert a series of tiff image into a mha
          file using SimpleRTK. Do you mean by writing a short program,
          or is it possible from the command line ? </div>
        <div><br>
        </div>
        <div>MG</div>
      </div>
      <div class="gmail_extra"><br>
        <div class="gmail_quote">2016-01-26 17:17 GMT-05:00 louie L <span
            dir="ltr"><<a moz-do-not-send="true"
              href="mailto:ghostcz@hotmail.com" target="_blank">ghostcz@hotmail.com</a>></span>:<br>
          <blockquote class="gmail_quote" style="margin:0 0 0
            .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div link="blue" vlink="#954F72" lang="EN-US">
              <div>
                <p class="MsoNormal">Hi MG,</p>
                <p class="MsoNormal"> </p>
                <p class="MsoNormal">Sometimes, the progressive
                  deformation from the center of rotation to the edge of
                  the image is caused by wrong sdd/sid ratio. Such as
                  change in the geometry will lead to distortion of the
                  image and wrong magnification.</p>
                <p class="MsoNormal">Maybe you can play with that
                  parameter and report your result. </p>
                <p class="MsoNormal"> </p>
                <p class="MsoNormal">Cheers,</p>
                <p class="MsoNormal">Louie</p>
                <p class="MsoNormal"> </p>
                <p class="MsoNormal">Sent from <a
                    moz-do-not-send="true"
                    href="http://go.microsoft.com/fwlink/?LinkId=550986"
                    target="_blank">Mail</a> for Windows 10</p>
                <p class="MsoNormal"><span
                    style="font-size:12.0pt;font-family:"Times New
                    Roman",serif"> </span></p>
                <div style="border:none;border-top:solid #e1e1e1
                  1.0pt;padding:3.0pt 0in 0in 0in">
                  <p class="MsoNormal" style="border:none;padding:0in"><br>
                    <b>From: </b><a moz-do-not-send="true"
                      href="mailto:simon.rit@creatis.insa-lyon.fr"
                      target="_blank">Simon Rit</a><br>
                    <b>Sent: </b>Tuesday, January 26, 2016 13:24<br>
                    <b>To: </b><a moz-do-not-send="true"
                      href="mailto:mgvallet.pro@gmail.com"
                      target="_blank">MG Vallet</a><br>
                    <b>Cc: </b><a moz-do-not-send="true"
                      href="mailto:rtk-users@public.kitware.com"
                      target="_blank">rtk-users@public.kitware.com</a><br>
                    <b>Subject: </b>Re: [Rtk-users] Sophia beads
                    reconstruction</p>
                </div>
                <div>
                  <div class="h5">
                    <p class="MsoNormal"><span
                        style="font-size:12.0pt;font-family:"Times
                        New Roman",serif"> </span></p>
                    <div>
                      <div>
                        <div>
                          <p class="MsoNormal"><span
                              style="font-size:12.0pt;font-family:"Times
                              New Roman",serif">Hi,</span><span
                              style="font-size:12.0pt;font-family:"Times
                              New Roman",serif"></span></p>
                        </div>
                        <p class="MsoNormal"><span
                            style="font-size:12.0pt;font-family:"Times
                            New Roman",serif">I think it's likely a
                            problem with parameters. The best would be
                            to obtain them from the Matlab code they
                            provide.</span></p>
                      </div>
                      <div>
                        <p class="MsoNormal"><span
                            style="font-size:12.0pt;font-family:"Times
                            New Roman",serif">Good luck,</span></p>
                      </div>
                      <p class="MsoNormal"><span
                          style="font-size:12.0pt;font-family:"Times
                          New Roman",serif">Simon</span></p>
                    </div>
                  </div>
                </div>
                <div>
                  <p class="MsoNormal"><span
                      style="font-size:12.0pt;font-family:"Times
                      New Roman",serif"> </span></p>
                  <div>
                    <div>
                      <div class="h5">
                        <p class="MsoNormal"><span
                            style="font-size:12.0pt;font-family:"Times
                            New Roman",serif">On Mon, Jan 25, 2016
                            at 5:48 PM, MG Vallet <<a
                              moz-do-not-send="true"
                              href="mailto:mgvallet.pro@gmail.com"
                              target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:mgvallet.pro@gmail.com">mgvallet.pro@gmail.com</a></a>>
                            wrote:</span></p>
                      </div>
                    </div>
                    <blockquote style="border:none;border-left:solid
                      #cccccc 1.0pt;padding:0in 0in 0in
                      6.0pt;margin-left:4.8pt;margin-right:0in">
                      <div>
                        <div class="h5">
                          <div>
                            <p class="MsoNormal"><span
                                style="font-size:12.0pt;font-family:"Times
                                New Roman",serif">Hi Simon,</span></p>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif"> </span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif">this was a
                                  point I missed. I had to do the log
                                  mapping.</span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif"> </span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif">I must say, I
                                  do not use RTK from shell. I just
                                  plugged the objects</span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif">FDKConeBeamReconstructionFilter
                                  and ThreeDCircularProjectionGeometry
                                  from RTK into a visualisation
                                  software. That's the reason I'm not
                                  absolutely sure about the length
                                  parameter setting.</span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif"> </span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif">Anyway, I'm now
                                  pretty close to your result. I believe
                                  the only difference is the progressive
                                  deformation of beads with the distance
                                  to center.</span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif"> </span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif">What's your
                                  opinion : is there another step I
                                  might have missed, or is it more
                                  likely a problem with parameters ?</span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif;color:#888888"> </span></p>
                            </div>
                            <div>
                              <p class="MsoNormal"><span
                                  style="font-size:12.0pt;font-family:"Times
                                  New Roman",serif;color:#888888">MG</span></p>
                            </div>
                          </div>
                        </div>
                      </div>
                      <div>
                        <div>
                          <div>
                            <p class="MsoNormal"><span
                                style="font-size:12.0pt;font-family:"Times
                                New Roman",serif"> </span></p>
                            <div>
                              <div>
                                <div class="h5">
                                  <p class="MsoNormal"><span
                                      style="font-size:12.0pt;font-family:"Times
                                      New Roman",serif">2016-01-21
                                      14:22 GMT-05:00 Simon Rit <<a
                                        moz-do-not-send="true"
                                        href="mailto:simon.rit@creatis.insa-lyon.fr"
                                        target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:simon.rit@creatis.insa-lyon.fr">simon.rit@creatis.insa-lyon.fr</a></a>>:</span></p>
                                </div>
                              </div>
                              <blockquote
                                style="border:none;border-left:solid
                                #cccccc 1.0pt;padding:0in 0in 0in
                                6.0pt;margin-left:4.8pt;margin-right:0in">
                                <div>
                                  <div>
                                    <div class="h5">
                                      <p class="MsoNormal"><span
                                          style="font-size:12.0pt;font-family:"Times
                                          New Roman",serif">Not
                                          exactly.
                                          rtk::FDKConeBeamProjectionFilter
                                          assumes that you pass the line
                                          integral (ln(I0/I)). But
                                          rtkfdk uses the
                                          ProjectionsReader to read the
                                          projections and converts them
                                          depending on the type: for mha
                                          or mhd, it just reads it and
                                          nothing else. For tif, it
                                          assumes that I is passed, try
                                          to guess I0 (or gets it from
                                          the cmd line) and computes
                                          ln(I0/I).<br>
                                          So from each tif projection,
                                          instead of letting them go
                                          through the ProjectionsReader
                                          in RTK, directly use the
                                          ImageReader, stack them and
                                          pass it to the reconstruction
                                          algorithm. In other words, if
                                          you use SimpleRTK, use
                                          ImageSeriesReader instead of
                                          ProjectionsReader.<br>
                                          Regarding the geometry, it
                                          would be nice to be confident
                                          in the geometry parameters,
                                          maybe from their Matlab code?<span
                                            style="color:#888888"><br>
                                            Simon</span></span></p>
                                    </div>
                                  </div>
                                  <div>
                                    <div>
                                      <div>
                                        <div class="h5">
                                          <p class="MsoNormal"
                                            style="margin-bottom:12.0pt"><span
                                              style="font-size:12.0pt;font-family:"Times
                                              New Roman",serif"> </span></p>
                                          <div>
                                            <p class="MsoNormal"><span
                                                style="font-size:12.0pt;font-family:"Times
                                                New Roman",serif">On
                                                21/01/2016 20:02, MG
                                                Vallet wrote:</span></p>
                                          </div>
                                        </div>
                                      </div>
                                      <blockquote
                                        style="margin-top:5.0pt;margin-bottom:5.0pt">
                                        <div>
                                          <div class="h5">
                                            <div>
                                              <p class="MsoNormal"><span
                                                  style="font-size:12.0pt;font-family:"Times
                                                  New Roman",serif">Hi
                                                  Simon and Cyril, </span></p>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"> </span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif">I
                                                    really appreciate
                                                    your insight.</span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"> </span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif">By
                                                    examining the
                                                    parameters of the
                                                    acquisition, I saw
                                                    that the center must
                                                    effectively be
                                                    offset (4.8 mm in
                                                    both directions).
                                                    For the attached
                                                    image, I also
                                                    increases sdd and
                                                    sid by a factor
                                                    1000, just in case I
                                                    would be wrong in
                                                    units. It reduces
                                                    the first default I
                                                    pointed out in my
                                                    first message. Also
                                                    note that my input
                                                    dataset was </span><span
                                                    style="font-size:9.5pt;font-family:"Times
                                                    New
                                                    Roman",serif">SophiaBeads_512_averaged.</span><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"></span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"> </span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:9.5pt;font-family:"Times
                                                    New
                                                    Roman",serif">Regarding
                                                    the
                                                    pre-processing mentioned by
                                                    Simon, I need more
                                                    help. Is it as
                                                    simple as the FDK
                                                    filter assumes that
                                                    the input is
                                                    intensity, but the
                                                    dataset provides
                                                    -ln(I/I0) ?</span><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"></span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"> </span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:9.5pt;font-family:"Times
                                                    New
                                                    Roman",serif">Regards,</span><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"></span></p>
                                              </div>
                                              <div>
                                                <p class="MsoNormal"><span
                                                    style="font-size:9.5pt;font-family:"Times
                                                    New
                                                    Roman",serif">mg</span><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif"></span></p>
                                              </div>
                                            </div>
                                          </div>
                                        </div>
                                        <div>
                                          <p class="MsoNormal"><span
                                              style="font-size:12.0pt;font-family:"Times
                                              New Roman",serif"> </span></p>
                                          <div>
                                            <div>
                                              <div class="h5">
                                                <p class="MsoNormal"><span
                                                    style="font-size:12.0pt;font-family:"Times
                                                    New
                                                    Roman",serif">2016-01-20
                                                    3:33 GMT-05:00 Simon
                                                    Rit <<a
                                                      moz-do-not-send="true"
href="mailto:simon.rit@creatis.insa-lyon.fr" target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:simon.rit@creatis.insa-lyon.fr">simon.rit@creatis.insa-lyon.fr</a></a>>:</span></p>
                                              </div>
                                            </div>
                                            <blockquote
                                              style="border:none;border-left:solid
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                                              6.0pt;margin-left:4.8pt;margin-right:0in">
                                              <div>
                                                <div class="h5">
                                                  <div>
                                                    <div>
                                                      <div>
                                                        <div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">Hi,</span></p>
                                                          </div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">I
                                                          quickly
                                                          checked
                                                          SophiaBeads_64_averaged.zip.
                                                          First, it
                                                          seems that
                                                          what is
                                                          provided is
                                                          directly the
                                                          line integral.
                                                          RTK will
                                                          process the
                                                          tif images as
                                                          if it were a
                                                          photon count
                                                          so I converted
                                                          the tif
                                                          projections to
                                                          mha to avoid
                                                          this. For the
                                                          conversion, I
                                                          used another
                                                          piece of
                                                          software but
                                                          you can easily
                                                          do the same
                                                          thing with
                                                          SimpleRTK.</span></p>
                                                        </div>
                                                        <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">Second,
                                                          I used the
                                                          enclosed
                                                          script which
                                                          gives me a
                                                          much better
                                                          result. I have
                                                          however a
                                                          geometry
                                                          problem. I
                                                          think they
                                                          provide a
                                                          Matlab piece
                                                          of code to get
                                                          the center of
                                                          rotation. If
                                                          you can run it
                                                          and find out
                                                          what is this
                                                          center, then
                                                          you can use it
                                                          to configure
                                                          the geometry
                                                          better with
                                                          the options
                                                          --proj_iso_x
                                                          and
                                                          --proj_iso_y.</span></p>
                                                      </div>
                                                      <p
                                                        class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">Good
                                                          luck,</span></p>
                                                    </div>
                                                    <p class="MsoNormal"><span
                                                        style="font-size:12.0pt;font-family:"Times
                                                        New
                                                        Roman",serif">Simon</span></p>
                                                  </div>
                                                </div>
                                              </div>
                                              <div>
                                                <div>
                                                  <div>
                                                    <p class="MsoNormal"><span
                                                        style="font-size:12.0pt;font-family:"Times
                                                        New
                                                        Roman",serif"> </span></p>
                                                    <div>
                                                      <div>
                                                        <div class="h5">
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">On
                                                          Tue, Jan 19,
                                                          2016 at 8:02
                                                          PM, MG Vallet
                                                          <<a
                                                          moz-do-not-send="true"
href="mailto:mgvallet.pro@gmail.com" target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:mgvallet.pro@gmail.com">mgvallet.pro@gmail.com</a></a>>
                                                          wrote:</span></p>
                                                        </div>
                                                      </div>
                                                      <blockquote
                                                        style="border:none;border-left:solid
                                                        #cccccc
                                                        1.0pt;padding:0in
                                                        0in 0in
                                                        6.0pt;margin-left:4.8pt;margin-right:0in">
                                                        <div>
                                                          <div
                                                          class="h5">
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">Thanks
                                                          Cyril! </span></p>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">going
                                                          to carefully
                                                          check my
                                                          inputs and I
                                                          give you some
                                                          news.</span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">mgv</span></p>
                                                          </div>
                                                          </div>
                                                          </div>
                                                        </div>
                                                        <div>
                                                          <div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          <div>
                                                          <div>
                                                          <div
                                                          class="h5">
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">2016-01-19
                                                          10:33
                                                          GMT-05:00
                                                          Cyril Mory
                                                          <<a
                                                          moz-do-not-send="true"
href="mailto:cyril.mory@uclouvain.be" target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:cyril.mory@uclouvain.be">cyril.mory@uclouvain.be</a></a>>:</span></p>
                                                          </div>
                                                          </div>
                                                          <blockquote
                                                          style="border:none;border-left:solid
                                                          #cccccc
                                                          1.0pt;padding:0in
                                                          0in 0in
                                                          6.0pt;margin-left:4.8pt;margin-right:0in">
                                                          <div>
                                                          <div>
                                                          <div
                                                          class="h5">
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">Hi,
                                                          <br>
                                                          <br>
                                                          It looks like
                                                          the geometry
                                                          is wrong
                                                          indeed,
                                                          because I have
                                                          never seen
                                                          such
                                                          artifacts.<br>
                                                          <br>
                                                          Hope that
                                                          helps,<br>
                                                          Cyril </span></p>
                                                          <div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"
style="margin-bottom:12.0pt"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">Le
                                                          19/01/2016
                                                          16:19, MG
                                                          Vallet a
                                                          écrit :</span></p>
                                                          </div>
                                                          </div>
                                                          </div>
                                                          <blockquote
                                                          style="margin-top:5.0pt;margin-bottom:5.0pt">
                                                          <div>
                                                          <div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">Dear
                                                          rtk-users, </span></p>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif">I
                                                          applied the </span><span
                                                          style="font-size:9.0pt;font-family:"Courier
New";color:black">FDKConeBeamReconstructionFilter to a data set
                                                          from </span><span
style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#333333"><a
moz-do-not-send="true" href="https://zenodo.org/record/16539"
                                                          target="_blank"><a class="moz-txt-link-freetext" href="https://zenodo.org/record/16539">https://zenodo.org/record/16539</a></a>. </span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#333333">This
                                                          is a plastic
                                                          tube filled
                                                          with glass
                                                          beads that has
                                                          been scanned.</span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#333333">Attached
                                                          is a view of
                                                          the
                                                          reconstructed
                                                          central slice.
                                                          It is found
                                                          that:</span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          </div>
                                                          <div>
                                                          <ol start="1"
                                                          type="1">
                                                          <li
                                                          class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#333333">the
                                                          beads are
                                                          quickly
                                                          deformed
                                                          outside the
                                                          center</span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></li>
                                                          <li
                                                          class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#333333">each
                                                          one has a
                                                          halo, or a
                                                          shadow (dont
                                                          know the
                                                          proper term)</span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></li>
                                                          </ol>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#333333">My
                                                          question is if
                                                          these are
                                                          simply
                                                          expected
                                                          artifacts. I
                                                          am not 100%
                                                          sure I
                                                          properly set
                                                          the geometry
                                                          parameters.</span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#333333">Regards,</span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          </div>
                                                          <div>
                                                          <p
                                                          class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial",sans-serif;color:#333333">mgv</span><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          </div>
                                                          </div>
                                                          <p
                                                          class="MsoNormal"
style="margin-bottom:12.0pt"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          </div>
                                                          </div>
                                                          <pre>_______________________________________________</pre>
                                                          <pre>Rtk-users mailing list</pre>
                                                          <pre><a moz-do-not-send="true" href="mailto:Rtk-users@public.kitware.com" target="_blank">Rtk-users@public.kitware.com</a></pre>
                                                          <pre><a moz-do-not-send="true" href="http://public.kitware.com/mailman/listinfo/rtk-users" target="_blank">http://public.kitware.com/mailman/listinfo/rtk-users</a></pre>
                                                          </blockquote>
                                                          <p
                                                          class="MsoNormal"
style="margin-bottom:12.0pt"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"><br>
                                                          <br>
                                                          </span></p>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          </div>
                                                          </div>
                                                          <span class="">
                                                          <table
                                                          style="border-collapse:collapse"
                                                          border="0"
                                                          cellpadding="0"
cellspacing="0">
                                                          <tbody>
                                                          <tr>
                                                          <td
                                                          style="padding:0in
                                                          11.25pt 0in
                                                          6.0pt">
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"></span></p>
                                                          <br>
                                                          </td>
                                                          <td
                                                          style="padding:.75pt
                                                          .75pt .75pt
                                                          .75pt">
                                                          <p><span
                                                          style="font-family:"Calibri",sans-serif;color:#3d4d5a">L'absence
                                                          de virus dans
                                                          ce courrier
                                                          électronique a
                                                          été vérifiée
                                                          par le
                                                          logiciel
                                                          antivirus
                                                          Avast. <br>
                                                          <a
                                                          moz-do-not-send="true"
href="https://www.avast.com/antivirus" target="_blank"><a class="moz-txt-link-abbreviated" href="http://www.avast.com">www.avast.com</a></a>
                                                          </span></p>
                                                          </td>
                                                          </tr>
                                                          </tbody>
                                                          </table>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          </span></div>
                                                          </blockquote>
                                                          </div>
                                                          <p
                                                          class="MsoNormal"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"> </span></p>
                                                          </div>
                                                          </div>
                                                        </div>
                                                        <span class="">
                                                          <p
                                                          class="MsoNormal"
style="margin-bottom:12.0pt"><span
                                                          style="font-size:12.0pt;font-family:"Times
                                                          New
                                                          Roman",serif"><br>
_______________________________________________<br>
                                                          Rtk-users
                                                          mailing list<br>
                                                          <a
                                                          moz-do-not-send="true"
href="mailto:Rtk-users@public.kitware.com" target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:Rtk-users@public.kitware.com">Rtk-users@public.kitware.com</a></a><br>
                                                          <a
                                                          moz-do-not-send="true"
href="http://public.kitware.com/mailman/listinfo/rtk-users"
                                                          target="_blank"><a class="moz-txt-link-freetext" href="http://public.kitware.com/mailman/listinfo/rtk-users">http://public.kitware.com/mailman/listinfo/rtk-users</a></a></span></p>
                                                        </span></blockquote>
                                                    </div>
                                                    <p class="MsoNormal"><span
                                                        style="font-size:12.0pt;font-family:"Times
                                                        New
                                                        Roman",serif"> </span></p>
                                                  </div>
                                                </div>
                                              </div>
                                            </blockquote>
                                          </div>
                                          <p class="MsoNormal"><span
                                              style="font-size:12.0pt;font-family:"Times
                                              New Roman",serif"> </span></p>
                                        </div>
                                      </blockquote>
                                      <p class="MsoNormal"><span
                                          style="font-size:12.0pt;font-family:"Times
                                          New Roman",serif"> </span></p>
                                    </div>
                                  </div>
                                </div>
                              </blockquote>
                            </div>
                            <p class="MsoNormal"><span
                                style="font-size:12.0pt;font-family:"Times
                                New Roman",serif"> </span></p>
                          </div>
                        </div>
                      </div>
                    </blockquote>
                  </div>
                </div>
                <p class="MsoNormal"><span
                    style="font-size:12.0pt;font-family:"Times New
                    Roman",serif"> </span></p>
                <p class="MsoNormal"> </p>
              </div>
            </div>
          </blockquote>
        </div>
        <br>
      </div>
    </blockquote>
    <br>
  </body>
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