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cad muppet
28th Sep 2007, 09:10 am
hi, i have a drawing which is already on national grid co-ordinates (eastings and northings) but have also been asked to put on longitude and lattitude co-ordinates. i have never done this before and not sure what to do.... can anybody help please.
i work on autocad 2008.
Alan Cullen
28th Sep 2007, 09:23 am
Google for some software called GDAY. It may be a good starting point. Otherwise consult your local friendly surveyor. Also check this thread, it may give you some pointers:

http://www.cadtutor.net/forum/showthread.php?t=14447&highlight=GDAY
mahahaavaaha
28th Sep 2007, 09:28 am
Hi,

from Adesk KB:(http://usa.autodesk.com/adsk/servlet/ps/item?siteID=123112&id=8161412&linkID=9240617)

Currently, you cannot enter longitude and latitude coordinates in AutoCAD®. However, you can input values in Surveyor Units (use the UNITS command).

So check the previous post's application (or others)

/Petri
Alan Cullen
28th Sep 2007, 09:46 am
GDAY should be able to convert known national grid coords to LAT/LONG (and vice-versa). Then it is just a matter of setting up a new grid on your drawing for LAT/LONG, based on those conversions.

Just get back to me if you are having problems. I love doing this stuff.
chulse
28th Sep 2007, 11:05 am
Alan-
Doesn't MAP have the ability to do this on the fly?
(this is not something I do regularly, and I'm more familiar doing reprojections in ArcGIS...)
Alan Cullen
28th Sep 2007, 11:18 am
chulse,

I think you would be better using ArcGIS. We have other software to do this. The only reason we use MAP is because Vanilla acad can't handle national mapping coords. So we don't really know the capabilities of MAP. We only use it to draw on national mapping grids. :lol:
chulse
28th Sep 2007, 11:23 am
chulse,

I think you would be better using ArcGIS. We have other software to do this. The only reason we use MAP is because Vanilla acad can't handle national mapping coords. So we don't really know the capabilities of MAP. We only use it to draw on national mapping grids. :lol:

Yeah, the main reason I got it was for import/export to/from GIS. It does support coordinate system re-projections and GIS file types, so for me it bridges some gaps. 95% of my clients use Autocad or Microstation...
Anyway, I've been playing with these features more lately and it's impressive what it can do compared to vanilla autocad. :)

Point is that Cad Muppet may want to look into it...
Alan Cullen
28th Sep 2007, 11:34 am
I agree. MAP is far different from Vanilla acad. The software we use is 12D Model. Acad doesn't even come close. We also have Civil 3D, and it doesn't come close. One day I would like you to tell me how to use MAP 3D to it's full affectiveness. Untill then, I will continue to use MAP as purely a drafting package, that can handle national mapping coords. :lol: