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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Dear Steve<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><p class=MsoNormal><span style='color:#1F497D'>></span>Yes. The sensor material needed for high temperatures isn't the same as the one for low temperatures, low temperatures are effectively invisible to them,.<br><br><span style='color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Makes sense. What do you think Damien can use? Is there a practical device working the 0-1200 range?<o:p></o:p></span></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0mm 0mm 0mm 6.0pt;margin-left:4.8pt;margin-right:0mm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>>></span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Yours must have 4 digits. Maybe more? How accurate is ‘precision’?</span><o:p></o:p></p></div></div></blockquote><div><p class=MsoNormal><br><span style='color:#1F497D'>></span>We have a good, pure graphite target, emissivity pretty damned close to one. Against type C thermometry, in a reducing atmosphere, at 1800C, we're close to +/- 25 C, we think. <br><br><span style='color:#1F497D'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>That is 1.2% (K). Pretty good at white heat.<o:p></o:p></span></p><p class=MsoNormal><br><span style='color:#1F497D'>></span>BEST measurement, in standards lab conditions (NIST, NPL) at these temps is only +/- 5 deg. <o:p></o:p></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><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>¼ of a %. Excellent. Steve Garrett provided me with some thermocouple suggestions for super accurate measurements but not at anything like that temperature. The Agilent 34972A can read them to 6½ digits, or pretends to! But of course that is not IR.<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><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Crispin <o:p></o:p></span></p></div></div></div></body></html>