Overview: Setting & Checking the Global Origin of a *.dgn File
This purpose of the following, is to guide you in setting the global origin of your MOF design file. Microstation does not support co-ordinates in a like most GIS packages. In fact it does not use projections, it uses a simple x y grid. For mapping each x, y position is associated with an x y position in the particular TM zone. For the province of British Columbia the grid is set up in such a way that lower left corner starts at a user specified origin known as the ‘Global Origin’, which ties into the size of the map sheet set to include particular UTM the zone. To summarise, when using BC Ministry of Forests data for mapping in Arc/Info you must specify your Global Origin, and your working units and then convert the data to an Arc coverage
Setting Your Global Origin:
- The BC global origin for UTM zone 10 is 4000:0:0, -5296000:0:0 (in the x and y)
To set this start Microstation and Open your MOF file.
Bring up the help and do a search on “Setting the global origin”Check the current Global origin by going to Menu Utilities->Key-in: In the Key-in text box type Active Origin$, have a look in the lower right corner of the design plane, and see if your origin is currently set to the 4:0:0, -5296:0:0. If it has been your work is finished.
If the origin has not been set you will need to specify it using by typing GO= 4000:0:0, -5296000:0:0, click “Key-in”As soon as you have entered these go to File Save-Settings to save the edits.Repeat step 4 and test if the origin has been set to the right values, if the values are not correct repeat set 5 and apply the (+-) to the numbers as needed. Again repeat steps 6. Keep going through these tests until you have the correct Global Origin.
Setting your Working Units:
- You will finally need to specify your map units. This step will setup the size of your page.
Go to Settings -> Design-file
Click on “Coordinate Readout” maintain the following settings
|Format: Working Unit
Click on “Working Units” maintain the following settings
|Master Units: m
Sub Units: mm
1 mm Per M
1000 Pos Units Per m
Working Area: 4294967
That should do it for now use FME Software downloadable from www.safe.com as a way of converting your Microstation file into a format specific for your GIS package!