<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html><head><meta http-equiv="content-type" content="text/html; charset=UTF-8"></head><body style="font-family:Arial;font-size:14px"><p>
Dear Kim,<br><br>
It is not easy to answer without the reconstructed images and reconstruction parameters. The option -TOF_reso will set up the Time of flight options in the datafile and assume the CRT of your Gate simulated system is 205.5 ps.<br><br>
You can potentially observe artifacts or noise increase if the TOF resolution does not match the actual resolution of the detectors. Additionnally, the convergence properties can change with time-of-flight (convergence is usually faster). This can lead to a worse SNR in the TOF reconstructed image than in the standard image for a same number of iterations, so it is worth to check SNR in image reconstructed with different number of iterations/subsets.<br><br>
Best regards,<br>
Thibaut<br><br><br>
김수환 <<a href="mailto:ksh2454178@naver.com">ksh2454178@naver.com</a>> a écrit :</p>
<blockquote style="border-left:2px solid blue;margin-left:2px;padding-left:12px;" type="cite">
<div style="font-size:10pt; font-family:Gulim, sans-serif;">
<p style='font-family: 돋움, Dotum, Helvetica, "Apple SD Gothic Neo", sans-serif; font-size: 12px;'>
<span style="font-size: 13.3333px;">Dear Castor users,</span></p>
<p style='font-family: 돋움, Dotum, Helvetica, "Apple SD Gothic Neo", sans-serif; font-size: 12px;'>
<span style="font-size: 13.3333px;"> </span></p>
<p style="">
<font face="돋움, Dotum, Helvetica, Apple SD Gothic Neo, sans-serif"><span style="font-size: 13.3333px;">(1) castor-GATERootToCastor -m LYSO.mac -s LYSO.root -TOF_reso 205.5 -vb 4 -src -o out2</span></font></p>
<p style="">
<font face="돋움, Dotum, Helvetica, Apple SD Gothic Neo, sans-serif"><span style="font-size: 13.3333px;">(2) </span></font><span style='font-family: 돋움, Dotum, Helvetica, "Apple SD Gothic Neo", sans-serif; font-size: 10pt;'>castor-GATERootToCastor -m LYSO.mac -s LYSO.root -vb 4 -src -o out2_v2</span></p>
<p>
<font face="돋움, Dotum, Helvetica, Apple SD Gothic Neo, sans-serif"><span style="font-size: 13.3333px;">I reconstructed the image using the two commands above.</span></font></p>
<p>
<font face="돋움, Dotum, Helvetica, Apple SD Gothic Neo, sans-serif"><span style="font-size: 13.3333px;">I measured the SNR after reconstruction.</span></font></p>
<p>
<font face="돋움, Dotum, Helvetica, Apple SD Gothic Neo, sans-serif"><span style="font-size: 13.3333px;">(1) is the time value is set and (2) is the time value is not set, but the SNR value of 2 is better than the value of 1.</span></font></p>
<p>
<font face="돋움, Dotum, Helvetica, Apple SD Gothic Neo, sans-serif"><span style="font-size: 13.3333px;">Why is that so?</span></font></p>
<p style="">
</p>
<p style='font-family: 돋움, Dotum, Helvetica, "Apple SD Gothic Neo", sans-serif; font-size: 12px;'>
<span style="font-size: 13.3333px;">Thanks for your help every time.</span></p>
<p style='font-family: 돋움, Dotum, Helvetica, "Apple SD Gothic Neo", sans-serif; font-size: 12px;'>
<span style="font-size: 13.3333px;">Best regards,</span></p>
<p style='font-family: 돋움, Dotum, Helvetica, "Apple SD Gothic Neo", sans-serif; font-size: 12px;'>
<span style="font-size: 13.3333px;"> </span></p>
<p style='font-family: 돋움, Dotum, Helvetica, "Apple SD Gothic Neo", sans-serif; font-size: 12px;'>
<span style="font-size: 13.3333px;">Suhwan Kim</span></p>
</div>
</blockquote>
<br><br></body></html>