Georeferencing a vector

[k_senthilnathan]

I have drawing file(utility drawings) which is in some unknown local coordiante system. I would like to convert it to LL83 ( I am working in Autodesk Map 2004). Any help would be greatly appreciated.

Nathan.

[JeremiahM]

First, is there anyway to find out what the parameters of the local coord system is? Map will allow you to create a custom coord system to match and then you can covert. Was the drawing surveyed? If so there should be some record of a known point that was used to controll the survey from. You will need to have some known point(s) in the drawing that you have a known coord system for in order to do an accurate transformation. If you have aerial imagery or GPS (mapping grade preferably) you could get it close, but that depends on the accruacy you need.

Jeremiah

[k_senthilnathan]

Jeremiah


I have street centerline file that I can georeference to the drawing. I tried "transform" but it did not align the drawing exactly. I also tried "rubber sheeting" and it doesn't do any good either. Is there a way to align the drawing to the street centerline data.

Nathan.

[JeremiahM]

Transform works best if you have know points that exist in both data sets, rubbersheeting is only used for "close enough". You really need some known points to be accurate, otherwise close enough will have to work, but I understand that doesnt work if you are using this for precise work.

Jeremiah