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------- Forwarded Message From: Wahner Paul Contr CSR 4500 <address@hidden> To: "'McIDAS Users List'" <address@hidden> Subject: GOES IR Calibration Date: Tue, 2 Dec 2003 18:22:17 -0000 Hello MUGgers, Question for the satellite experts out there. The GOES User's Guide (1983) makes reference to the "Standard IR Calibration Table" (Fig. 7-2). This table correlates count values to temperatures. Is the information in this table valid for GOES-12? If not, is there another table published somewhere that is? Thanks. Paul Wahner MIDDS Systems Engineer/ Meteorologist CSR 4500, Cape Canaveral Air Force Station address@hidden (Com) 321.853.8184 (Fax) 321.853.8291 (DSN) 467.8184 From: Dave Santek <address@hidden> Date: Tue, 02 Dec 2003 12:57:27 -0600 To: address@hidden Subject: Re: GOES IR Calibration Paul, I think the 1983 guide is for 8-bit counts....not the 10-bit counts for the current satellites. But, when you display an image, the conversion from temperature to grayscale [8-bit] uses that standard IR table. This is the default in McIDAS for all IR sensors on all satellites. dave From: Erik Johnson <address@hidden> To: address@hidden Date: 02 Dec 2003 14:39:07 -0500 Paul- Michael Weinreb, et. al. authored a document that outlines the calculations for converting raw GVAR counts to radiance and temperature values. Look-up tables for correlating counts w/ physical values for GOES 8-12 are also included towards the end of the document. "Conversion of GVAR Infrared Data to Scene Radiance or Temperature" http://www.oso.noaa.gov/goes/goes-calibration/gvar-conversion.htm GOES 12 IR Imager lookup table: http://www.oso.noaa.gov/goes/goes-calibration/docs/goes12_img_side1_lut Hope this helps. cheers, Erik Johnson CLASS developer TMC Technologies