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I have raster displaying Lat/ Long grid, but map information shows that, it s been mapped in Gauss Krugger projetion/ Beijing 1954. So, technically we need to geo reference the map in Gauss Krugger/ Beigjing 1954 Projectec Coordinated System in ArcGIS.

So, basically what I need to do is, georeference raster by input of Lat/Long, but need to update the georeferencing by projected coordinated system mentioned above.

In Global mapper, we can load the raster and enter Lat/Long available in the map, straight away it will be recalculated to Projected coordinated system.

Can we get anything same in ArcGIS?

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  • Do you want answers relating to QGIS (because you added the tag but don't mention it in the question text)?
    – underdark
    Commented May 22, 2014 at 13:57
  • Yeah,. would be more helpfull.. underdark..
    – Satish
    Commented May 22, 2014 at 14:01

2 Answers 2

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The lat/lon grid is called a graticule. Although it shows degrees, minutes and seconds it's not, it is projected to the map coordinate system in order to flatten it out to get it on paper, it's only a reference to geographical coordinates.

To georeference to this create your grid in DD (fishnet works) or instructions as per Creating lat/lon grid in QGIS? and then project it to Gauss Krugger projetion/ Beijing 1954 to use as reference points or for QGIS or ArcMap you can just set the coordinate system of the layers (data frame) prior to georeferencing and either will project on the fly.

I did this for years with 1:250k and 1:100k maps.

There is nothing wrong with georeference in Global Mapper, QGIS and I think ERDAS still does it, so long as a world file is written... it doesn't matter which you use.

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Got an answer for ArcGIS from ESRI Support...

"You are quite correct that the raster should be georeffed into its real projected system. But if you have a graticule on the map marked in GCS you can enter these cords directly. After clicking on the "from" point using the GeoRef toolbar, if you right click, it gives you the opportunity to type in the known coords of the point in DMS or DD, these locations are then immediately projected into the PCS units, and will appear in the link table as metres or whatever it is..This is particularly useful when georeffing scanned map sheets where the corners are usually marked in Lat/Long but the map is UTM or whatever"

Can I get the same sort of things in QGIS??

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