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Hello Sadek,<br><br>
It could be due to the update factors of your data being too low for the optimizer thresholds during the first iterations. These thresholds (which can be changed in <em>conf/optimizer/</em> depending on the algorithm you use) are there to avoid division by 0 or voxels being trapped in a very low value. This could happen with datasets with low statistic, or if the values in your sensitivity image are high in comparison with the image-based correction values of the first updates. In this case, using an appropriate calibration factor in your datafile header could improve this.<br><br>
Hope this helps!<br>
Thibaut<br><br>
Sadek Nehmeh <<a href="mailto:san2028@med.cornell.edu">san2028@med.cornell.edu</a>> a écrit :</p>
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Dear All,</p>
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I wish everyone a happy and prosperous 2021!</p>
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At many occasions, I get flat images (same small value for all pixels in the FOV). Sometimes this gets fixed after few iterations. Is anyone getting similar issues? Any reason or fix for that?</p>
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Thanks,</p>
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Sadek</p>
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