gis info and project alignment

[mike_raplee]

Trying for the third time, somehow I keep switching to the basic autocad forum.   Anyway.   I have downloaded some aerials and some data from

Ohio.gov.  My problem is the project alignment doesn't  match up with the aerials.  Why doesn't it line up?

The first thing I would add is that alignment has not changed.  I thought maybe that I had assigned the wrong coordinate system so I tried to change the coordinate system.  That didn't solve the problem either.  I am sure it is something I am not doing correctly but, I have no other guesses as to what it might be.

Any ideas?

Thanks in advance,

Mike

[rl_jackson]

Version and SP would help.

When you say shift are we speaking of something really large or small.

Anything I've done in OH has been in NAD 83 Feet if that's of any help, just need to verify North or South Zone.

[mike_raplee]

In the grand scheme of things I guess you would say relatively small,but enough I am not sure it is as useful as it could be. I am looking at it being shifted about 90' to the west and 38' to the south. Civil 3d 2015 sp2 Mike Raplee Concrete Division Construction Engineer 310 Blacketor Drive Rochester, IN 46975 Phone: (574) 224-2815 Mobile: (317) 501-0101 Fax: (574) 223-2768 mike.raplee@ebpaving.com www.ebpaving.com The information in this email is confidential. Access to this email by anyone else is unauthorized. If you are not the intended recipient, or believe that you have received this communication in error, please do not print, copy, retransmit, disseminate, or otherwise use the information. Also, please indicate to the sender that you’ve received this email in error, and delete the copy you received. The recipient should check this email and any other attachments for the presence of viruses, as E&B Paving accepts no liability for any damage caused by any viruses transmitted by this email. Further, E&B paving accepts no liability for the content of this email, or for the consequences of any actions taken on the basis of the information provided, unless that information is subsequently confirmed in writing. *Please consider the environment before you print.*

[Pointdump]

Mike,

Shifting to the SouthWest in that amount sounds like a US Survey Foot/International Foot problem. Easy way to find out is to multiply your northing and easting by .000002 and see if you get about 38' and 90' respectively.

Further than that we need to see your drawing and data.

Dave

[rl_jackson]

No to say this will help, but attached is a zip fle with a word document directly from the OGRIP site. This discusses there accepted datums/projections. As well as provides information for using a WMS connection verse a direct download.

Could there be a possiblity that you have say the Alignment in on datum (like 27) and the image in another (probably 83) this could cause a shift. But most states I've dealt with made drastic shift in the coordinate systems XY when switching to 83.

You could also do a comparision of LAT LONG values in your drawing as compared to Google Earth, just to see if you can determine the culprit.

But it seems like you need to verify your datum matches the projects.