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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Sean Larkin [mailto:sean.larkin@lickenbrocktech.com] <br><b>Sent:</b> Friday, October 14, 2011 4:14 PM<br><b>To:</b> 'Bill Lorensen'<br><b>Subject:</b> RE: [vtkusers] vtkImageReader - SetDataSpacing - What is it doing?<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>That’s what I’m thinking as well. I understand that if the pixel spacing is larger the opacity may change, which would change the rendered image. But , if I adjust the opacity function I can never get as good an image as with larger pixel spacing. Maybe with smaller pixel spacing there are fewer rays cast to produce the image?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Bill Lorensen <a href="mailto:[mailto:bill.lorensen@gmail.com]">[mailto:bill.lorensen@gmail.com]</a> <br><b>Sent:</b> Friday, October 14, 2011 3:42 PM<br><b>To:</b> Sean Larkin<br><b>Cc:</b> <a href="mailto:vtkusers@vtk.org">vtkusers@vtk.org</a><br><b>Subject:</b> Re: [vtkusers] vtkImageReader - SetDataSpacing - What is it doing?<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I suspect that the volume mapper has some settings that are specified in physical units.<br><br><br>On Friday, October 14, 2011, Sean Larkin <<a href="mailto:sean.larkin@lickenbrocktech.com">sean.larkin@lickenbrocktech.com</a>> wrote:<br>> Hello,<br>><br>> I’m using vtkImageReader to loading a 3D volume and render it with vtkVolumeMapper. I want to be able to adjust the voxel aspect ratio, so I decided to use the SetDataSpacing() method of vtkImageReader. Is this the best way to do this? I ask this because I can get very different looking rendered images when I use the same aspect ratio, with different values. For example, when I set the spacing to [.043,.043,1] I get poor resolution compared to when I use [1,1,23.3] (these are the same ratios). Does anyone know why this is happening?<br>><br>> <br>><br>> Thanks,<br>><br>> Sean Larkin <o:p></o:p></p></div></body></html>