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Hi Randy: This issue is now in JIRA at: https://bugtracking.unidata.ucar.edu/browse/TDS-538 So I am closing this support ticket. Hopefully we will get a resolution soon. John > John: > > Once again, its me. > > I hav touched base with Martin Raspaud about the sweep_angle_axis parameter > discrepancy. The sweep angle axis discussion in the note of the #72 track > ticket item is correct and the proj.4 web-site > (http://trac.osgeo.org/proj/wiki/proj%3Dgeos) is incorrect. Martin has > submitted a request to get it fixed. > > very respectfully, > > randy > > > On Dec 6, 2013, at 6:54 AM, Randy Horne <address@hidden> wrote: > > > John: > > > > It is me again. I think the redlines to the 1999 CGMS spec I provided you > > have a sign error. I will chase this to ground. > > > > v/r > > > > rh > > > > > > On Dec 5, 2013, at 9:19 PM, Randy Horne <address@hidden> wrote: > > > >> John: > >> > >> (1) > >> I don't know what the issue is with the eumetsat site. > >> > >> I think the document can also be found at: > >> > >> http://www.cgms-info.org/docs/default-source/technical-publications/cgms-lrit-hrit-global-specification-(v2-8-of-30-oct-2013).pdf?sfvrsn=8 > >> > >> The equations in this document are for the meteosat satellite > >> geostationary projection. I have attached redlines to the equations > >> needed for the GOES geostationary projection. Note that the redlines were > >> applied to the 1999 version of the LRIT-HRIT global specification. > >> > >> > >> (2) > >> The projection has already been implemented by the Europeans in the proj.4 > >> library. checkout: > >> > >> http://trac.osgeo.org/proj/wiki/proj%3Dgeos. > >> > >> Note that after looking it over, there appears to be a discrepancy in how > >> the sweep_angle_axis is interpreted. I sent an email to Martin Raspaud, > >> the guy who developed the geostationary projection s/w for prom.4, This > >> sweep_angle_axis is what distinguishes the meteosat geostationary > >> projection from the GOES geostationary projection. > >> > >> (3) > >> I have a very good description of the GOES variant of the geostationary > >> projection and I also have a pretty well document excel spreadsheet that > >> implements the mapping between geostationary projection fixed grid > >> coordinates and lat/lon. Let me know if you want them. > >> > >> v/r > >> > >> rh > >> > >> > >> <LRIT_HRIT_Projection_GOES_modification.pdf> > >> > >> > >> On Dec 5, 2013, at 5:52 PM, "Unidata netCDF Java Support" <address@hidden> > >> wrote: > >> > >>> Hi Randy: > >>> > >>> Im starting to look at this, and I see that > >>> > >>> http://www.eumetsat.int/idcplg?IdcService=GET_FILE&dDocName=PDF_CGMS_03&RevisionSelectionMethod=LatestReleased. > >>> > >>> from > >>> > >>> https://cf-pcmdi.llnl.gov/trac/ticket/72 > >>> > >>> is giving a 404. Do you have a copy of that doc? > >>> > >>> John > >>> > >>> > >>> > >>>> Lansing et al: > >>>> > >>>> How are you ? Randy Horne here. > >>>> > >>>> I am following up on an email I sent you 7 months ago regarding the > >>>> recently added "geostationary" projection. sorry for the delay, but > >>>> things took WAY longer than anticipated . > >>>> > >>>> I finally have a decent "geostationary" projection dataset. There is an > >>>> extra attribute added by the NetCDF library s/w because we are not > >>>> creating variables in the correct order, but hopefully it should not > >>>> affect your testing. > >>>> > >>>> The file I am sending you is of the continental United States from the > >>>> GOES East slot at -75 degrees east longitude. Note that the y and x > >>>> coordinate variables are scaled integers. Also note that there is a "t" > >>>> dimension, which is set to 1, that is in the process of being removed > >>>> from the product because it is superfluous. > >>>> > >>>> The resolution of the data is approximately 1 kilometer (28 micro > >>>> radians from the perspective of the satellite to be exact). The GOES-R > >>>> system will be generating imagery at a variety of resolutions. > >>>> > >>>> In addition to making available a netCDF file (.nc), I am also making > >>>> available a png file so you can see what it looks like without using > >>>> netCDF tools. The image has plenty of contrast so it should be good > >>>> enough to verify the geostationary projection s/w you are writing works > >>>> properly. Let me know if you need any additional information on the > >>>> geostationary projection…I have plenty of info that I can send you. > >>>> > >>>> The .nc and .png files are available from the Harris Corporation > >>>> web-site. Here are the addresses you can paste into the browser URL > >>>> field. > >>>> > >>>> ftp.harris.com/pub/incoming/test.nc > >>>> > >>>> ftp.harris.com/pub/incoming/test.png > >>>> > >>>> > >>>> I understand you guys are probably busy with other things, but when you > >>>> get around to it, I would appreciate it if you let me know how things > >>>> work out with the dataset and the geostationary projection s/w you guys > >>>> are writing. > >>>> > >>>> > >>>> very respectfully, > >>>> > >>>> randy > >>>> > >>>> > >>>> > >>>> > >>>> On Apr 25, 2013, at 7:53 PM, Randy Horne <address@hidden> wrote: > >>>> > >>>>> Lansing: > >>>>> > >>>>> Our I&T team is still working to put a "good" product file together. > >>>>> > >>>>> Sorry about the delay. > >>>>> > >>>>> As soon as we have a good/representative product file, I will let you > >>>>> know. > >>>>> > >>>>> > >>>>> very respectfully, > >>>>> > >>>>> randy > >>>>> > >>>>> > >>>>> On Apr 10, 2013, at 5:24 PM, Unidata netCDF Java Support wrote: > >>>>> > >>>>>> Hi Randy, > >>>>>> > >>>>>> John Caron is out of the office for a conference, but I'll step in and > >>>>>> say "yes," we'd like sample data sets. I don't know how much he has > >>>>>> done, but we'll need the files regardless. Where would they be > >>>>>> available? > >>>>>> > >>>>>> Regards, > >>>>>> Lansing Madry > >>>>>> Unidata > >>>>>> Boulder, Colorado > >>>>>> > >>>>>>> Dear Sir: > >>>>>>> > >>>>>>> My name is Randy Horne. I am working the GOES-R ground segment > >>>>>>> program. > >>>>>>> > >>>>>>> I am a member of the cf_metadata and cf_satellite message groups. > >>>>>>> > >>>>>>> Last year, I was an active participant in the establishment of a new > >>>>>>> earth projection to support data received from geostationary > >>>>>>> satellites. > >>>>>>> > >>>>>>> This new projection is "geostationary" and was approved. > >>>>>>> > >>>>>>> Shortly after it was approved, I believe Jon Caron (one of your guys) > >>>>>>> worked on the "geostationary" projection software. He asked us for > >>>>>>> some > >>>>>>> test data sets, but at the time we did not have any. > >>>>>>> > >>>>>>> I had the impression Jon Caron was writing this software so Unidata > >>>>>>> could add this new projection to the list of projections currently > >>>>>>> supported (see > >>>>>>> > >>>>>>> http://www.unidata.ucar.edu/software/netcdf-java/v4.2/javadoc/ > >>>>>>> > >>>>>>> Currently, the "geostationary" projection is not listed on this web > >>>>>>> page. > >>>>>>> > >>>>>>> Can you provide me a status of where this effort is? > >>>>>>> > >>>>>>> Note that we now have test data sets available should they be needed. > >>>>>>> > >>>>>>> very respectfully, > >>>>>>> > >>>>>>> randy > >>>>>>> > >>>>>>> > >>>>>> > >>>>>> > >>>>>> Ticket Details > >>>>>> =================== > >>>>>> Ticket ID: ZCD-209044 > >>>>>> Department: Support netCDF Java > >>>>>> Priority: Normal > >>>>>> Status: Open > >>>>>> > >>>>> > >>>>> > >>>>> ____________________________________ > >>>>> > >>>>> Randy C. Horne (address@hidden) > >>>>> Principal Engineer, Excalibur Laboratories Inc. > >>>>> voice & fax: (321) 952.5100 > >>>>> url: http://www.excaliburlabs.com > >>>>> > >>>>> > >>>>> > >>>>> > >>>> > >>>> > >>>> ____________________________________ > >>>> > >>>> Randy C. Horne (address@hidden) > >>>> Principal Engineer, Excalibur Laboratories Inc. > >>>> voice & fax: (321) 952.5100 > >>>> url: http://www.excaliburlabs.com > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> > >>> > >>> Ticket Details > >>> =================== > >>> Ticket ID: ZCD-209044 > >>> Department: Support netCDF Java > >>> Priority: Urgent > >>> Status: Open > >>> > >> > >> > >> ____________________________________ > >> > >> Randy C. Horne (address@hidden) > >> Principal Engineer, Excalibur Laboratories Inc. > >> voice & fax: (321) 952.5100 > >> url: http://www.excaliburlabs.com > >> > >> > >> > >> > > > > > > ____________________________________ > > > > Randy C. Horne (address@hidden) > > Principal Engineer, Excalibur Laboratories Inc. > > voice & fax: (321) 952.5100 > > url: http://www.excaliburlabs.com > > > > > > > > > > > ____________________________________ > > Randy C. Horne (address@hidden) > Principal Engineer, Excalibur Laboratories Inc. > voice & fax: (321) 952.5100 > url: http://www.excaliburlabs.com > > > > > > Ticket Details =================== Ticket ID: ZCD-209044 Department: Support netCDF Java Priority: Critical Status: Closed