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</o:shapelayout></xml><![endif]--></head><body lang=DE link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi,<o:p></o:p></p><p class=MsoNormal><span lang=EN-GB>for my Master’s thesis I am testing some implementations for a 4D reconstruction of small mice set. For this I apply the rooster algorithm on the full projection set with a discretised phase signal. To compare the rooster reconstruction I also take a subset of the full set with rtksubselect considering the phase signal and apply the regularized conjugate gradient reconstruction algorithm on that subset of projections. This way I get a 3D reconstruction for each phase respectively.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>However with the same gamma_space=8e-6 (in regularized cg gammatv defined) in the total variation step both in rooster and regularized conjugate gradient and gamma_time equal to 0 in roosters algorithm, I do not get the same results. The rooster reconstruction is much more blurried compared to the regularized conjugate gradient reconstruction, which surprises me. Shouldn’t be both reconstructions nearly identical under same conditions? Outer and inner loops (n_iter=30, tv_iter=10, cg_iter=4) are equally set. The blurriness occurs only in respiratory phases with small amount of projections (approx. 90)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>For visualization I have added an example to the following link: <a href="https://gigamove.rz.rwth-aachen.de/d/id/P42uxboh472jzV">https://gigamove.rz.rwth-aachen.de/d/id/P42uxboh472jzV</a><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB>The regularized conjugate gradient reconstruction is shown on both upper images and the rooster reconstruction is shown on both lower images.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>I appreciate any help or explanation.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>Erwin<o:p></o:p></span></p></div></body></html>