[postgis-users] TIGER & SRID

[Michael Welter]

Thank you very much, Randy.

Randy George wrote:
> Hi Michael,
> 
> 4269 matches current TIGER for most of the US but Hawaii and Territories may
> need to have a conversion. Interestingly there is no info in the regional
> datum used currently? If you are using historical TIGER before 1995, 4267 or
> a conversion to 4269 would work. It's probably easier to keep everything the
> same so 4269 would be the best. Hawaii could be stored in 4269 and queried
> out in UTM or a regional coordinate system like 102661 thru 102665
> 
> 
> Here is the note in the TIGER docs:
> 
> " In the 1995 and later TIGER/Line files, NAD83 is the coordinate datum
> used for the 48 contiguous states, the District of Columbia, Alaska, Puerto
> Rico, and the Virgin Islands of the United States. Regional datums are
> used for Hawaii and the Pacific Island Areas. NAD27 was the coordinate
> datum used for the 1994 and earlier versions of the TIGER/Line files
> except in Hawaii and the Pacific Island Areas where regional datums were
> used. Because the datum used was not relevant to the U.S. Census
> Bureau's purposes for creating maps, the documentation did not record
> the specific datum of our source material for Hawaii and the Pacific Island
> Areas."
> 
> Here is the 4269 ref:
> 4269	EPSG	4269
> GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS
> _1980",6378137,298.257222101]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532
> 92519943295]]	+proj=longlat +ellps=GRS80 +datum=NAD83
> 
> rkgeorge
> 
> -----Original Message-----
> From: postgis-users-bounces at postgis.refractions.net
> [mailto:postgis-users-bounces at postgis.refractions.net] On Behalf Of Michael
> Welter
> Sent: Tuesday, May 01, 2007 5:47 AM
> To: PostGIS Users Discussion
> Subject: [postgis-users] TIGER & SRID
> 
> I'm loading some lat/lon coordinates from TIGER into a PostGIS database. 
>   Is 4269 the proper SRID for this data?
> 
> Thanks,
> 
> 
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-- 
Michael Welter
Telecom Matters Corp.
Denver, Colorado US
+1.303.414.4980
mike at TelecomMatters.net
www.TelecomMatters.net