Inquiry Tool - Point Co-ordinate Conversion

[phil_mcdevitt]

Hi All,

I am trying to convert a point to Latitude and Longitude so I can build a model of an area in Infraworks.

In the Civil 3D file I have selected the local co-ordinate system which is in Malaysia.

In Civil 3d I select the Inquiry Tool, then Points, Point Inverse, then choose Point Co-ordinate 1 (see attached).

I then snap to a point in the drawing but the co-ordinates are not converting to Latitude and Longitude.

I have also attached a reduced version of the Civil 3D file.

Regards

Phil

[Pointdump]

Phil,

Try the Geodetic Calculator:

 

Dave

[phil_mcdevitt]

Thanks Dave,

Gave it a try, the co-ordinates are sending me to France when I should be in Malaysia, not sure what is happening.

[Pointdump]

Phil,

I'll bet France is nice this time of year, but let's find out what's happening. Can you post your drawing?

Oh, and what are "brchaintrunc" units?

Dave

[Pointdump]

Phil,

I guess the problem is the units. Why would C3D include a Coordinate System that uses units you can't select? I looked up British Chains, which are the same as American Gunter Chains. 1 Chain = 20.1168 Meters. If your Units are set to Meters that would wildly affect your location.

Dave

[Pointdump]

Phil,

If you divide your Local Northing and Easting by 20.1168, you'll at least land somewhere in that Kertau Coordinate System:

Dave

[AllenJessup]

Strange. 0.5° by 98° seems to be in the correct area.

[cwr-pae]

Something is wrong where you enter it to your map. The lat and long should be instantly recognizable as a point on the equator an half way around the world from the meridian, say in line with Mongolia / western China, that's no where near France or any part of Europe.

@AllenJessup  Just to be ****, you misread his coordinates, its S 0 0' 34" not N 0.5.  About a step and a half globally.

[AllenJessup]

I was looking at the second image and misread it. I saw Malaysia on the map and got excited. Weird coincidence that what I misread got in the right area.

[cwr-pae]

Globally, a half minute and a half degree aren't that much difference. Less than 50 miles between the points I think.

[Pointdump]

Phil,

I tried several times to wring correct Lats and Longs out of that Kertau Coordinate System, but was unable. I had to conclude that Coordinate System is broken, at least in my 2016 version.

Dave

[phil_mcdevitt]

Thanks for your input everyone,

I think whatever is producing the co-ordinates needs re-calibrating. I can zoom to the area I need this time as I know where it is.

If I need to use the co-ordinates in the future to find my way I could end up anywhere.

Regards

Phil

[razkaman]

i can't open your file cause im using 2017. but i don't think its the right coordinate. if you try with google earth, try find Kertau, Malaysia. and go to tools , select option and change long/lat in 3d view tab , with Universal transerve mercator. and you can see that area is far from your NE.

[phil_mcdevitt]

Hi Razkaman,

I saved the file back, you should be able to open it now. (attached)

Regards

Phil

[razkaman]

Thank you Phil. i already take a look, i try to map export that file with various project zone in malaysia, kertau 48N , kertau 47N. then i import it to google earth. and all the shp file is on the ocean near malaysia in different location. i can't use the project zone kertau/malaya and other zone that have kertau in it. 

Could it possibly that from the first they import to infraworks/civil 3D , it use incorrect zone? 

[phil_mcdevitt]

Hi Razkaman,

The contour file was given to us by the surveyor, and the co-ordinate system stated as  below :

Really not sure what the story is, I had to leave it, was wasting too much time on it. Thanks for your input.

Regards

Phil

[razkaman]

i also use it , but i can't import shp file with google earth if i use that project zone. but it okay with kertau 48N, 47N. maybe they should change the project zone with 48N. after all Malaysia & Indonesia usually use UTM - WGS84 . and kertau location is based on 48N.