<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hello Rukiah,<div class=""><br class=""></div><div class="">in GATE the source is independent from the geometry. </div><div class="">So the voxel dimensions (matrix size and voxel size) of the source do not need to be the same as your voxelized geometry.</div><div class=""><br class=""></div><div class="">In the example page 18, I think they suggest using a lower resolution geometry compared to the source to speed up the simulation.</div><div class="">Be careful though, if you do so, the scoring resolution (with a DoseActor for example) will also be lower (the DoseActor is recommended to have the same dimensions as the geometry).</div><div class=""><br class=""></div><div class="">If you don’t mind the computation time I suggest you use the same source and geometry dimensions, so it’s easier to match the source locations with the phantom geometry (you can use the same image input to define both).</div><div class=""><br class=""></div><div class="">Best regards,</div><div class=""> Maxime Chauvin</div><div><br class=""><blockquote type="cite" class=""><div class="">On 26 Jun 2019, at 02:33, Rukiah <<a href="mailto:katoshka_7880@yahoo.com" class="">katoshka_7880@yahoo.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div class=""><div class="ydp5494c5e7yahoo-style-wrap" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><div class=""><div class="">Hi Gate-users,</div><div class=""><br class=""></div><div class="">I have a query on the strategy to develop a voxelized phantom based on the training material page 18 below:</div><div class=""><a href="http://www.opengatecollaboration.org/sites/default/files/Talk4.pdf" class="">http://www.opengatecollaboration.org/sites/default/files/Talk4.pdf</a></div><div class="">It was shown that the attenuation image does not necessarily have the same volume with the emission image in terms of voxel size and matrix size. How it could be? Will it induce any mismatch mapping especially at the border of tissues? My understanding is the attenuation image must have the same matrix and voxel size with emission image so that the GATE can map the emission distribution correctly due to the same scale of both images. Have anyone experienced this issue and can clarify this?<br class=""></div><div class=""><br class=""></div><div class="">Thank you.<br class=""></div><div class="ydp5494c5e7signature"><div class=""><font face="bookman old style, new york, times, serif" color="#00007f" class=""></font> </div><font size="3" class=""><em class=""><var id="ydp5494c5e7yui-ie-cursor" class=""></var></em></font><div style="margin: 5px 0px; padding: 0px; border-color: rgb(204, 204, 204); border-style: solid; border-width: 1px; min-height: 0px; line-height: 0; font-size: 0px;" class="ydp5494c5e7hr"></div></div></div></div></div>_______________________________________________<br class="">Gate-users mailing list<br class=""><a href="mailto:Gate-users@lists.opengatecollaboration.org" class="">Gate-users@lists.opengatecollaboration.org</a><br class="">http://lists.opengatecollaboration.org/mailman/listinfo/gate-users</div></blockquote></div><br class=""></body></html>