Polar Stereographic Geotiff doesn't display

[wstraka]

I can read in a polar stereographic geotiff into the Omni Viewer, but I can't display it in the Display window. Given the various polar applications, it would be nice to be able to read in these types of geoTiffs.

[bobc]

Hello -

Can you please post an example polar stereographic geotiff file to pub/incoming so I can have a look? Please let me know when you post the file as well as the file name.

Thanks -
Bob Carp
McIDAS User Services

[Bernie Connell]

Along the same lines as this inquiry, I saw that there could be a source input of tif, gif, or jpg. I tried importing a geotiff that I output by McIDAS and I have the corner coordinates for, but the only way it seems to display is in the omni viewer. What is the OMNI viewer and can I put a map on it and overlay other data?

[Rick]

Hi Bernie,

You should be able to load geotiff files using the General Files/Directories chooser and then display the data as an Image Display. If I read your post correctly, you may have created the geotiff file with McIDAS-X. If that is the case, you should be able to display the file with more than just the omni display. Please post your geotiff file so we can try it out here.

Rick

[Bernie Connell]

I'll preface this with - I've used McIDAS much more than I have used McIDAS-V.
In terms of trying to read in the file, I've tried a number of things with various outcomes. if I go with General, Files/Directories and then choose image gif, jpg, png, it only lets me display with omni control and puts a color table on it. This original image is black and white.
If I go with General, Flat files, I can put in Dimensions and Navigation, and it will come up with Display choices which are 1) Imagery with 3 color and 3 color over topography 2 Data probe/Time series (which goes into never never land if selected) and 3) Omni control. When I do select 3 color image (which it is not), I get an error that the file is not an image.

[Rick]

I was able to load the file using TIFF files for the Data Type. I did have to change the projection to North America and then zoom in on the data.

[Bernie Connell]

Thanks - that works. I had looked for geotiff and thought I had looked for tiff as well, but didn't see it.

[joleenf]

Hi,

I am seeing the same thing with my data. I can only view the data via the omni controls. I tried

1.) Loading with "I'm Feeling Lucky'
2.) Loading as a Tiff file
3.) Using the Flat Files Chooser. (did not load into field selector this way)

I downloaded the data from the National Snow and Ice Data Center. I have placed an example at

ftp://ftp.ssec.wisc.edu/pub/ssec/joleen/

Joleen

[joleenf]

And I found some documentation which seems to indicate that the auxillary file does not contain the lat/lon, I need to track down some lat/lon files which were not included in the zipped data and hopefully that will solve the display navigation.

http://nsidc.org/data/docs/noaa/g02156_ ... #latlon_fn

Joleen

[bobc]

Hi Joleen -

I tried your file in McIDAS-V through the General>Files/Directories chooser with the 'Tiff files' data type and I ran into the same problem that you did, only the Omni Control display type is available. I ran your file through the GeoTIFF tool in ToolsUI, and there does appear to be geographical information in there:

21 IFDEntry == tag = 34735 (GeoKeyDirectoryTag) type = SHORT count = 56 values = 1 1 0 13 1024 0 1 1 1025 0 1 1 2048 0 1 0 2052 0 1 9001 2054 0 1 9102 3072 0 1 32767 3074 0
geoKey = 1024 (GTModelTypeGeoKey) value = 1 (Projected)
geoKey = 1025 (GTRasterTypeGeoKey) value = 1 (Area)
geoKey = 2048 (GeographicTypeGeoKey) values = 0
geoKey = 2052 (GeogLinearUnitsGeoKey) values = 9001
geoKey = 2054 (GeogAngularUnitsGeoKey) value = 9102 (Degree)
geoKey = 3072 (ProjectedCSTypeGeoKey,) value = 32767 (UserDefined)
geoKey = 3074 (ProjectionGeoKey,) values = 32767
geoKey = 3075 (GeoKey_ProjCoordTrans) values = 15
geoKey = 3076 (ProjLinearUnitsGeoKey) value = 9001 (Meter)
geoKey = 3081 (GeoKey_ProjNatOriginLat) values = 60.0
geoKey = 3082 (GeoKey_ProjFalseEasting) values = 0.0
geoKey = 3083 (GeoKey_ProjFalseNorthing) values = 0.0
geoKey = 3095 (ProjStraightVertPoleLongGeoKey) values = -80.0
22 IFDEntry == tag = 34736 (GeoDoubleParamsTag) type = DOUBLE count = 4 values = 60.0 0.0 0.0 -80.0

Some of these 'geoKey' lines are different than what I'm seeing in other GeoTiff files that I have on my machine that work fine in McIDAS-V. The other GeoTiffs I have were created in McIDAS-X from AREA files, and it looks like yours was created in IDL.

As for the approach of bringing in the Tiff file through the Flat Files chooser, we have seen problems in the past trying to work with projections that aren't Rectilinear. From looking at the display of data through the Omni Control display, as well as looking at the AUX file in WordPad, it appears that this data is in a Polar Stereographic projection. Adding the ability to work with different projections through the Flat Files chooser has been written up as Inquiry 1717.

I will write up an inquiry for your GeoTiff file not working correctly in McIDAS-V. I'm not exactly sure what the data is that you ordered from the National Snow and Ice Data Center, so I'm not sure what format(s) are available. We have had users successfully work with binary formatted data from NSID before that could be loaded in through the Flat Files chooser.

Thanks -
Bob Carp