topic Re: Wrong georeferencing in AutoCAD Map 3D Forum

Wrong georeferencing

nikola.boskovic2 — Sat, 18 Feb 2023 13:55:10 GMT

Hi, i live in Montenegro and we use EPSG code 8678. That code is equal to EPSG code 31276 but in autocad 3d map 2021 is not like that. A few days earlier when use code 8678 is great but after update that is not the same. Now with that code I get arial picture 1 mile to right side. What is the problem and how can solve this?

Re: Wrong georeferencing

Pointdump — Sat, 18 Feb 2023 15:30:11 GMT

Hi Nikola,
I can't find EPSG:31276.
Are you using Bing Live Maps or do you have georeferenced images?
Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sat, 18 Feb 2023 15:37:41 GMT

I use BING map. That code is in "Not filter selected"

Re: Wrong georeferencing

Pointdump — Sat, 18 Feb 2023 16:31:39 GMT

Nikola,
Check the extents of EPSG:8678 in MAPCSLIBRARY. Occasionally they're not correct. You can change the extents >>>This Way<<<. Please post a screen shot of the map being off. Is it like this?
Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sat, 18 Feb 2023 16:52:13 GMT

it's same

Re: Wrong georeferencing

Pointdump — Sat, 18 Feb 2023 17:18:34 GMT

Nikola,
That sure looks like a Datum shift, from MGI_1901 to WGS84:
>>>EPSG:8678<<< shows this:
TOWGS84[682,-203,480,0,0,0,0]],
(682 Meters East and 203 Meters South)

Can you post your shapefile? (Zip together DBF,PRJ,SHX,SHP)

Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sat, 18 Feb 2023 17:24:39 GMT

I don't have shp file, this is dwg (geodetic file). I use map for better orientation.

Re: Wrong georeferencing

Pointdump — Sat, 18 Feb 2023 17:26:13 GMT

Nikola,

Can you post the drawing?

Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sat, 18 Feb 2023 17:35:22 GMT

because file is to large I send a part of them

Re: Wrong georeferencing

Pointdump — Sat, 18 Feb 2023 18:53:51 GMT

Nikola,
Just now opening up your drawing. Thanks for posting it.
Your drawing is set to Imperial (Foot) Units.

EPSG:8678 is a Metric Coordinate System.
Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sat, 18 Feb 2023 20:27:16 GMT

How can get that window for configuration in 3D MAP?

Re: Wrong georeferencing

Pointdump — Sat, 18 Feb 2023 20:57:06 GMT

Nikola,
Sorry, I forgot you don't have Civil 3D. In Map 3D and Vanilla AutoCAD use Command -DWGUNITS.
Dave

Re: Wrong georeferencing

Pointdump — Sun, 19 Feb 2023 00:25:07 GMT

Nikola,
I experimented with several different coordinate systems, and BOSNIA-6M-S9 came closest. 460 Meters off.
I guess you need to ask whoever you got this linework from what the coordinate system is.
Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sun, 19 Feb 2023 08:01:43 GMT

I appreciate you trying but this didn't solve my problem. This work before windows update, I doubt that it is due to an update, but I don't know where to look for those settings

Re: Wrong georeferencing

Pointdump — Sun, 19 Feb 2023 08:21:06 GMT

Nikola,
I grabbed a road shapefile and dropped it into your drawing with EPSG:8678 assigned. Note they do not match. Where did you get your drawing?
Shapefile attached.
Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sun, 19 Feb 2023 08:54:03 GMT

the drawing is from the geodetic cadastre. All lines is 100% correct with dimensions and that work before win update. The booth EPSG code are approximately the same.

Re: Wrong georeferencing

Pointdump — Sun, 19 Feb 2023 11:16:00 GMT

Nikola,
Can you post the original geodetic cadastre drawing, or even better, a link to where you got it? If the drawing is over 71MB you can use WeTransfer or DropBox link.
I don't doubt that all lines are 100% correct, but they are not correctly located. I suspect a Datum difference, MGI_1901 to WGS84.
I don't know how a Windows update could cause this problem, but stranger things have happened, so maybe.
Dave

Re: Wrong georeferencing

nikola.boskovic2 — Sun, 19 Feb 2023 13:08:59 GMT

I solved the problem by reinstalling the operating system. In any case, I thank you for your help and advice