Hi Nyoman,<div><br></div><div>Each volume of the CSD file contains one of the SH coefficients, as documented on the csdeconv help page. When you say only the first 6 volumes have contrast, do you mean the others are zero, or just look like noise? If the latter, that's what you expect, since these volumes contain the l=4 and higher harmonics, which are noisy. They still contribute high angular frequency information though, and hence contribute to the angular resolution - much like the outer edges of k-space contribute edge information, even though they appear noisy. </div>
<div><br></div><div>Cheers,</div><div><br></div><div>Donald.</div><div><br><br><div class="gmail_quote">On 15 June 2012 17:51, Nyoman Kurniawan <span dir="ltr"><<a href="mailto:nyoman.kurniawan@cai.uq.edu.au" target="_blank">nyoman.kurniawan@cai.uq.edu.au</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div style="direction:ltr;font-size:10pt;font-family:Tahoma">Dear Donald,<br>
Could you tell us what information is contained within each volume in the CSD files?<br>
For example, I used max harmonic order 6 and saw there are 28 volumes, and it looks that the first 6 volumes have some contrast?<br>
<br>
Regards,<br>
Nyoman<br>
<br>
</div>
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<br></blockquote></div><br><br clear="all"><div><br></div>-- <br>Jacques-Donald Tournier (PhD)<br>Brain Research Institute, Melbourne, Australia<br>Tel: +61 (0)3 9035 7033<br>
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