Make sure your layers align properly before importing them in the DB and don't 
forget to answer Guido's question...

> -----Original Message-----
> From: Jason Mathis [mailto:[email protected]]
> Sent: Wednesday, May 14, 2014 12:35 PM
> To: Pierre Racine; PostGIS Users Discussion
> Subject: RE: [postgis-users] getting raster values for point from st_value
> 
> Its NAD83/Conus Albers
> http://epsg.io/5070
> 
> I needed to reproject the shape file as well. It was originally in an Albers
> projection but before handed over to me was projected into wgs84. The
> raster and shape files did not line up properly until we reprojected the
> shape file first and then did the conversion to raster.
> 
> I had some issues with the reprojection as well and someone on the gdal
> mailing list suggested using the epsg:5070 for the reprojection. So the
> whole process really went
> 
> 1. reproject shapfile
> 2. create raster files
> 3. Import files in the database
> 
> I just reprojected one file using 4269 and it fits in the extents. Although 
> the
> point is still hanging out there.
> 
> I created the point like:
> 
>   SELECT ST_Transform(ST_SetSRID(ST_MakePoint(-111.750185,
> 34.886948),5070),5070)::geometry(Point,5070)
> 
> Which should be in arizona.
> 
> 
> 
> On May 14, 2014 at 9:52:31 AM, Pierre Racine ([email protected])
> wrote:
> 
> 
>       What is this -s 5070 that you put in your raster2pgsql command?
> Should not it be 4269 (NAD 83)?
> 
>       > -----Original Message-----
>       > From: Jason Mathis [mailto:[email protected]]
>       > Sent: Wednesday, May 14, 2014 11:47 AM
>       > To: Pierre Racine; PostGIS Users Discussion
>       > Subject: RE: [postgis-users] getting raster values for point from
> st_value
>       >
>       > Well I was visualizing the tiff file not the postgis raster table. Its
> seems
>       > somewhere along the lines the qgis raster plugin dropped off.
> Although I am
>       > able to see the raster tables in the db manager and can drag/drop
> the table,
>       > horribly slow but works.
>       >
>       >
>       > The raster extents or just the raster table do not overlay with the
> point,
>       > which explains the problem. I still don’t understand what I did
> wrong.
>       > Attaching a screen shot.
>       >
>       > thanks,
>       >
>       >
>       >
>       > On May 14, 2014 at 7:01:27 AM, Pierre Racine
> ([email protected])
>       > wrote:
>       >
>       >
>       > You said you could visualize this table in QGIS? Or were you
>       > speaking about a shapefile? You can visualize the rastextets table
> and the
>       > points table the same way.
>       >
>       > Pierre
>       >
>       > > -----Original Message-----
>       > > From: Jason Mathis [mailto:[email protected]]
>       > > Sent: Tuesday, May 13, 2014 6:30 PM
>       > > To: PostGIS Users Discussion; Pierre Racine
>       > > Subject: Re: [postgis-users] getting raster values for point from
>       > st_value
>       > >
>       > > Hi Pierre,
>       > >
>       > > Thanks so much for super quick response. You will have to
> forgive
>       > me I am
>       > > fairly new to postgis.
>       > >
>       > > Creating the table is no problem but how would I check if it
>       > overlaps with
>       > > my points?
>       > >
>       > > thanks!
>       > >
>       > >
>       > >
>       > > On May 13, 2014 at 4:08:40 PM, Pierre Racine
>       > ([email protected])
>       > > wrote:
>       > >
>       > >
>       > > Create a new table with the extents of the raster tiles and check
> if
>       > it
>       > > overlaps with your points:
>       > >
>       > > CREATE TABLE rastextets AS
>       > > SELECT rast::geometry
>       > > FROM tbl_raster
>       > >
>       > > Pierre
>       > >
>       > > > -----Original Message-----
>       > > > From: [email protected] [mailto:postgis-
>       > > users-
>       > > > [email protected]] On Behalf Of Jason Mathis
>       > > > Sent: Tuesday, May 13, 2014 5:56 PM
>       > > > To: [email protected]
>       > > > Subject: [postgis-users] getting raster values for point from
>       > > st_value
>       > > >
>       > > > Hi all,
>       > > >
>       > > > I have recently loaded a good amount of rasterized shape files
>       > into
>       > > a db. I
>       > > > mainly used gdal_rasterize and raster2pgsql. The shape files
>       > were
>       > > in NAD83
>       > > > so I used the below commands to rasterized and load.
>       > > >
>       > > > gdal_rasterize -at -a desc -where "desc='Very High'" -burn 2 -tr
>       > 30
>       > > 30 -ot
>       > > > byte -a_nodata -99 shape_file.shp raster.tiff
>       > > > raster2pgsql -d -s 5070 -t 100x100 -F -I -C -Y raster.tiff
> tbl_raster
>       > |
>       > > psql -d
>       > > > raster_db
>       > > >
>       > > > I had two sets of shape files one set had about 10 burn values
>       > and
>       > > another
>       > > > had about 50. The issue is getting these values out of the
> raster.
>       > I
>       > > believe I
>       > > > should be using something from this page:
>       > > > http://postgis.net/docs/RT_ST_Value.html.
>       > > >
>       > > > I can visualize this file in QGIS and it looks good, the histogram
>       > > shows
>       > > > values. I can also use the postgis functions, st_summarystats
> or
>       > > > st_histogram to see some data but I need to be able to query
> a
>       > > given point
>       > > > and return the raster value.
>       > > >
>       > > > I have this:
>       > > >
>       > > > SELECT ST_Value(rast,(ST_Point( -111.750185, 34.886948)))
>       > > > FROM tbl_raster
>       > > > WHERE st_intersects(rast, (ST_Point(-111.750185,
> 34.886948)))
>       > > >
>       > > > Then i thought oh wait should I set the srid?:
>       > > >
>       > > > SELECT ST_Value(rast,(ST_SetSRID(ST_Point( -111.750185,
>       > > > 34.886948),5070)))
>       > > > FROM tbl_raster
>       > > > WHERE st_intersects(rast, (ST_SetSRID(ST_Point(-111.750185,
>       > > > 34.886948),5070)))
>       > > >
>       > > > Still I get nothing, then I thought I need to transform so I got
>       > this:
>       > > >
>       > > > SELECT ST_Value(rast,(ST_Transform(ST_SetSRID(ST_Point( -
>       > > 111.762866,
>       > > > 34.874309),5070),4326)))
>       > > > FROM tbl_raster
>       > > > WHERE st_intersects(rast,
> (ST_Transform(ST_SetSRID(ST_Point(
>       > -
>       > > > 111.762866, 34.874309),5070),4326)))
>       > > >
>       > > > But in the end nothing.
>       > > >
>       > > > I did need to add the SRID to the spatial_ref_sys table:
>       > > >
>       > > > INSERT into spatial_ref_sys (srid, auth_name, auth_srid,
>       > > proj4text, srtext)
>       > > > values ( 5070, 'EPSG', 5070, '+proj=aea +lat_1=29.5
> +lat_2=45.5
>       > > +lat_0=23
>       > > > +lon_0=-96 +x_0=0 +y_0=0 +ellps=GRS80
>       > > +towgs84=0,0,0,0,0,0,0
>       > > > +units=m +no_defs ', 'PROJCS["NAD83 / Conus
>       > > >
>       > >
>       >
> Albers",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHER
>       > > > OID["GRS
>       > > >
>       > >
>       >
> 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],TOWGS84[0,
>       > > >
>       > >
>       >
> 0,0,0,0,0,0],AUTHORITY["EPSG","6269"]],PRIMEM["Greenwich",0,AUTHORIT
>       > > >
>       > >
>       >
> Y["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG
>       > > >
>       > >
>       >
> ","9122"]],AUTHORITY["EPSG","4269"]],PROJECTION["Albers_Conic_Equal_
>       > > >
>       > >
>       >
> Area"],PARAMETER["standard_parallel_1",29.5],PARAMETER["standard_par
>       > > >
>       > >
>       >
> allel_2",45.5],PARAMETER["latitude_of_center",23],PARAMETER["longitude
>       > > > _of_center",-
>       > > >
>       > >
>       >
> 96],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["
>       > > >
>       > >
>       >
> metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUT
>       > > > HORITY["EPSG","5070"]]’);
>       > > >
>       > > > But ultimately I have nothing I can’t seem to get any data out
>       > > using a query
>       > > > with a point value. I am thinking it has to do with the srid?
> Since
>       > I
>       > > can
>       > > > visually inspect it and see data.
>       > > >
>       > > > Anyone have any hot ideas as to why I am not seeing data?
>       > > >
>       > > > Thanks!
>       > > >
>       > > >
>       > > >
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>       > >
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> 
> 
> 
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