Jump to content
lisagravy

Georeferencing settings

Recommended Posts

We are running a webinar on this on 20th March. Initially, this was planned to be exclusive to our Service Select customers, but I am looking to open this up to everyone. As soon as I have the registration mechanics in place, I will post them on the forum.

 

  • Like 3

Share this post


Link to post

This is a very interesting too indeed.

 

I tried to use it last week but due to the time pressure and a vague clue on how to use it I decided to give it ago another time.

What I managed to check on my drawing was the alignment with the ortophotomap underlay. They seemed to be miles away. I understand that I need to align my UCS with the GCS.

Again I understand that in VW, an imported dwg file retains its NE coordinates from the survey but is just centered on the drawing space.

There are geodesic station points with [lat lon] coordinates on the topo survey drawing, therefore I should be able to use these for georeferencing, correct? 

Should that be done through the Document Georeferencing or one should change the internal origin first?

Any step by step walktrough?

Share this post


Link to post

Here's my high level overview.

  1. Open blank document.
  2. Edit document georeferencing settings and choose the appropriate geographic coordinate system. If you are in the UK, the standard UK templates are automatically set to 27700 which is the geographic coordinate system equivalent to the OS British National Grid. On this dialogue, the coordinates at the top relate to the position of the file's INTERNAL origin, within that coordinate system. In a UK file, we set this to the Greenwich Meridian as a default. This can be changed.
  3. Import the DWG file, but use the checkbox This file contains georeferenced geometry. Click the Advanced button and take a look at the GIS tab - this will confirm that the DWG will be brought into the georeferencing settings set at the document level. Click OK and again to complete the import. 
  4. The geometry will land in the correct place within the GIS system (as long as it was actually created in the correct place in the first place.)
  5. Use the Geoimage tool and draw a rectangle around the site. This will load the imagery associated with the site.
  6. Use the Geolocate tool and click on a location on the site to move the internal origin close to the geometry.
  7. From this point on, X and Y are no longer relevant, and you should use Easting and Northing instead. The GIS Stake tool can be used to report these.
  8. If you want the numbers on the User Coordinate system to match, use Tools > Origin > User Origin. Choose the option to Set the user origin to match the origin of the geographic coordinate system.

Why might it not work?

  • Your DWG is not created in the same coordinate system as the GIS coordinate system.
  • Like 1

Share this post


Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


 

7150 Riverwood Drive, Columbia, Maryland 21046, USA   |   Contact Us:   410-290-5114

 

© 2018 Vectorworks, Inc. All Rights Reserved. Vectorworks, Inc. is part of the Nemetschek Group.

×
×
  • Create New...