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Transformation Parameters between WGS84 and Nord Tunisie Projection

May 13 2010 | 1 comment
Categories: Map Data

I am trying to georeferencing some charts from Tunisia with the corner coordinates in wgs84. My project uses the Nord Tunisie projection:
Projection: Lambert_Conformal_Conic
False_Easting: 500000,000000
False_Northing: 300000,000000
Central_Meridian: 11,000000
Standard_Parallel_1: 40,000000
Scale_Factor: 0,999626
Latitude_Of_Origin: 40,000000
Linear Unit: Meter

I would like to know wich are the correct geographic transformation parameters from wgs84 to to the GCS_Carthage?

My geographic data is at the north part of Tunisia.
Thank you!

Mapping Center Answer:

There is a Carthage_To_WGS_1984 transformation that you can use for this. (If you are mapping an area offshore, then use the Carthage_To_WGS_1984_2 transformation instead.)

On the "Choosing an appropriate transformation" page of the online help, there is a link at the bottom to a list of the available transformations, methods, and areas of use -- it is the geographic_transformations.pdf file.

More on the specifics. posted by Jaynya Richards on May 13 2010 2:32PM
Our Projection Specialist responded with the following:
ESRI (and EPSG) only have two Carthage to WGS 1984 transformation. #1 is a general one defined by the US Defense Mapping Agency (now the NIMA). and #2 is of 'offshore' and was calculated by ELF. It has similar parameter values to #1. Your particular parameters are in grads, not degrees --just please keep this in mind.

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