topic Georeference CAD data in Data Management Questions

Georeference CAD data

Anonymous User — Tue, 31 Aug 2010 21:21:12 GMT

Original User: alnesbit

Hello all,

I'm using 9.3.1 ArcInfo.

Ok, I read how to georeference CAD data. I have been doing it that way for a while. But there has to be a better way...Anyone?

I read why I can't have more than 2 control points. And I understand that. But I'm having to open the dwg in CAD and plotting a pdf, then creating a tiff from the pdf. Then georeferencing the tiff in ArcMap to the aerial and then trying to get the CAD dwg at least close to that. Then recreating all of the data from the tiff into a geodatabase by manual editing. Then creating annotation from the CAD. Then going back and moving the annotation to where it should be.

So, why can't I have the option of a different kind of transformation with CAD data? Is it hard to program the software or something?

What do other people do when they have this problem? I finally got to a point where I would like a better way, but I don't think there is one. ugh.

Thanks for your ideas,

Re: Georeference CAD data

AnantThunuguntla — Wed, 08 Sep 2010 21:24:06 GMT

Hello all,

I'm using 9.3.1 ArcInfo.

Ok, I read how to georeference CAD data. I have been doing it that way for a while. But there has to be a better way...Anyone?

I read why I can't have more than 2 control points. And I understand that. But I'm having to open the dwg in CAD and plotting a pdf, then creating a tiff from the pdf. Then georeferencing the tiff in ArcMap to the aerial and then trying to get the CAD dwg at least close to that. Then recreating all of the data from the tiff into a geodatabase by manual editing. Then creating annotation from the CAD. Then going back and moving the annotation to where it should be.

So, why can't I have the option of a different kind of transformation with CAD data? Is it hard to program the software or something?

What do other people do when they have this problem? I finally got to a point where I would like a better way, but I don't think there is one. ugh.

Thanks for your ideas,

Hi Andrea,

If you would like to use more than 2 points for transformation ,you can use the Import from CAD tool to convert the CAD Drawing to a Geodatabase. You can then perform the desired transformations say Rubbersheeting on this data.

We allow only 2 point similarity transformations just to preserve the aspect ratio of the CAD dataset.

Re: Georeference CAD data

Anonymous User — Thu, 09 Sep 2010 15:30:52 GMT

Original User: alnesbit

ideas website: https://c.na1.visual.force.com/apex/ideaView?id=0873000000087QpAAI

I don't want to preserve the aspect ratio of the CAD dataset, I want to match it to the aerial.

You're talking about the tool "Import from CAD" right? Have you tried to do it this way? It's horrible. I just did it and it created line, point, area. It didn't keep the layer names in the attribute table or the symbology the same as the CAD drawing. I don't know what is what.

so I guess the way I'm doing it is the only decent way as of right now. sigh

Re: Georeference CAD data

AnantThunuguntla — Thu, 09 Sep 2010 19:07:53 GMT

Sorry about the above suggestion. Can you try the Feature class to Feature class tool.

If this doesn't help, can you call up tech support, they should be able to help you out.