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Hi Gautam, I have relayed your questions about values from multiple detectors to the McIDAS support folks at SSEC (I could not come to a definitive conclusion after reading the McIDAS Programming Reference Manual). It is my observation that it is likely that you will need RAW GOES images to get the information you need (many images stored in AREA format are pre-calibrated). To determine if you have pre-calibrated or RAW images, do the following: IMGLIST group/descriptor BAND=n FORM=ALL (NB: substitute group/descriptor with your ADDE dataset group and descriptor names; substitute 'n' for hte appropriate band number) In the listing, you should see 'cal type:'. The value of this tells you if the image is calibrated or RAW. Here is an example output: IMGLIST WEST/CONUS BAND=1 FORM=ALL Image file directory listing for:WEST/CONUS Pos Satellite/ Date Time Center Res (km) Image_Size sensor Lat Lon Lat Lon --- ------------- ------------ -------- ---- ---- ----- ----- ------------ 31 G-10 IMG 12 APR 06102 18:45:00 33 132 Band: 1 0.65 um VIS Cloud and Surface Features 1.33 0.59 3932 x11416 proj: 0 created: 2006102 184515 memo: RT GVAR type:GVAR cal type:RAW offsets: data= 3328 navigation= 256 calibration= 2816 auxiliary= 0 doc length: 228 cal length: 0 lev length: 0 PREFIX= 232 valcod: 102184500 zcor: 0 avg-smp: N start yyddd: 2006102 start time:184515 start scan: 331 lcor: 2645 ecor: 10053 bytes per pixel: 2 ss: 74 Resolution Factors (base=1): Line= 1.0 Element= 1.0 IMGLIST: done A partial answer to your third question: > Thirdly, if it possible to have an image with multiple bands? Yes. The McIDAS AREA file can be used to store single and multibanded images. Images sent in the Unidata IDD 'UNIWISC' (aka MCIDAS) datastream are all single banded. I will get back to you with the information that SSEC provides about extracting detector information from an AREA file. > I am a new user of McIDAS and the archive on the Support webpage have been > extremely helpful so far. I am trying to use GOES-12 imager data for my > research > and need to calibrate the data to get reflectance ( for VIS ) and temperature > ( for IR ). I have also looked at the conversion table and formulas provided > at > the below mentioned webpage. > http://www.oso.noaa.gov/goes/goes-calibration/index.htm. > > The calibration for both VIS and IR depend on the detector number. I am > unable to figure > out that in an AREA#### file, under DATA block, what is the sequence of > detector in each > line. > > Data block is suppose to like the following: > > line prefix 1 line data 1 line prefix 2 line data 2 etc > |_____________|______________| _____________|___________|.... > > > Firstly, if I have AREA0001, which contains only VIS band, how is the data > from > detector placed > > 1) Is it like this Becuase of Side 1 configuration of GOES-12 ? > DEC_5 DEC_6 DEC_7 DEC_8 DEC_1 DEC_2 DEC_3 DEC_4 ... > > 2) Or any other arrangement? > > Secondly, similarly what is the detector arrangement when I have only one IR > band. > DEC_2_a DEC_2_b DEC_2_a DEC_2_b ... etc > > Thirdly, if it possible to have an image with multiple bands? And if so, how > are the dectotors arranged in that case. > > Any help or relevant reference in this regard is appreciated. > > Thanks, > Gautam. Cheers, Tom **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: LFB-979507 Department: Support McIDAS Priority: Normal Status: Closed