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Hi Gautam, re: > Thank you for forwarding my question to other ppl. No worries. We always bounce McIDAS questions back to SSEC when we can't answer them. > I did determine > the images I have on my local server were 'RAW' images. > > IMGLIST GOES12/VIS.3 FORM=EXP > Image file directory listing for:GOES12/VIS > Pos Satellite/ Date Time Center Res (km) > Image_Size > sensor Lat Lon Lat Lon > --- ------------- ------------ -------- ---- ---- ----- ----- > ------------ > 3 G-12 IMG 12 APR 06102 21:32:00 > Band: 1 0.65 um Visible - Cloud Cover > 480 x 640 > proj: 0 created: 2006102 214420 memo: RT GVAR > type:GVAR cal type:RAW > offsets: data= 3328 navigation= 256 calibration= 2816 > auxillary= 0 > doc length: 0 cal length: 0 lev length: 0 PREFIX= 0 > valcod: 0 zcor: 0 avg-smp: N > start yyddd: 2006102 start time:213144 start scan: 355 > lcor: 2837 ecor: 9277 bytes per pixel: 2 ss: 78 > Resolution Factors (base=1): Line= 1.0 Element= 1.0 > IMGLIST: done Very good. Unfortunately, it takes a bit more to get images that have the necessary information. Here is the information I received from SSEC: The detector information is in the documentation section of the AREA files, so if they used IMGCOPY, they had to use DOC=YES. The XRD command GVARINFO gives the detector information - look for the value lidet. There are 2 detectors for the IR channels. The same detector number applies to line of either single- or multi-band IR. A note for visible data, we use an average of the 8 detector calibration coefficients. Why? Because the visible sensors are not continually calibrated and their response degrades over time. There are some empirical coefficients to correct for this, based on the length of time the sensor has been in operation. The XRD (X Research and Development) application that is referred to is included in the Unidata McIDAS-X distribution. It is not, however, built/installed by default. After you have completely built McIDAS-X, you will need to create the GVARINFO executable and help file as follows: <as 'mcidas'> cd ~mcidas/mcidas2005/src make gvarinfo.k gvarinfo.hlp ln gvarinfo.k ~/bin ln gvarinfo.hlp ~/help You then run 'HELP GVARINFO' from the McIDAS Text and Command window (or run 'help.k GVARINFO' from the Unix command prompt while logged in as 'mcidas' or any other user whose Unix environment has been configured to run McIDAS). > Also, of the various dataset available (ALL, CONUS, FD, NH, OTHER, > SH) for GOES-East/West, is the difference between them is only the > various map re-projection ? The projections are all the same (assuming that you are getting the images from datasets like PUB EAST or WEST from UNIDATA2.SSEC.WISC.EDU. The difference is the region that the sector covers; the projection is the same in all. Question: where are you getting your images from? > If so, which one of them is the one that > the satellite sees (level_0) ? All RAW images reflect what the satellite sees. > In the operational configuration for GOES-12, the GVAR scan output > for visible band is such Detector 5 is northmost, followed by 6,7 8, > 1, 2, 3 and 4. Thus I am thinking if the level_0 data is known then > the arrangement of the detectors might be know like this (One whole > line corresponds to one detector and not as I earlier thought) > > line: Dec_5_ele_1 Dec_5_ele_2 ...... > line: Dec_6_ele_1 Dec_6_ele_2 ...... > line: Dec_7_ele_1 Dec_7_ele_2 ...... > line: Dec_8_ele_1 Dec_8_ele_2 ...... > line: Dec_1_ele_1 Dec_1_ele_2 ...... > line: Dec_2_ele_1 Dec_2_ele_2 ...... > line: Dec_3_ele_1 Dec_3_ele_2 ...... > line: Dec_4_ele_1 Dec_4_ele_2 ...... > > I might be completely wrong about it. Thank you for your help. As was pointed out in the message sent by SSEC to me regarding your inquiry, the detector-specific information is contained in the document part of the image. If you are creating the AREA files using IMGCOPY from a remote server that has the RAW data, you must include the DOC=YES keyword sequence when creating the local image (and you need to create a local image to use GVARINFO since this application does not use ADDE). 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