Importing Field Book Files

[bsimonsen]

After having recently adopting C3D, we have come across a serious glitch in our methodology. Our drawing template has "U.S. Survey Foot" set in the imperial-metric conversion toggle (drawing settings). When we import field books, the coordinates of database points match the field book file coordinates, but the points in the drawing are "transformed" - distance depends on how far we are from the system origin, up to six feet in some of our topo. If we set the survey database units to "U.S. Survey Foot", then both points in the database and drawing are "transformed". Only when both settings are set to "International Foot" do the point coordinates all match the field book file coordinates. Problem is, all field work is done in units of "U.S. Survey Foot", as is often required by state code. What are we missing? Where is the setting that tells C3D the field book file was collected in units of "U.S. Survey Foot"? This was never an issue for us in Land Development.

[sinc]

Do you have your data collector set to work in US Survey Foot?

The units you used during data collection should be in a line in your FBK file. For International Feet, you typically see a line like:

UNIT FOOT DMS

For US Survey Foot, you should see something like:

UNIT USFOOT DMS

[bsimonsen]

Thanks. All our files had previously used "FOOT" as the unit identifier. Wonder why we never had problems in Land?

I will try "USFOOT".

[bsimonsen]

Thanks SINC. It was as simple as that. I really appreciate your rapid response.

[sinc]

Thanks. All our files had previously used "FOOT" as the unit identifier. Wonder why we never had problems in Land?

I'm not sure... I actually never used FBK files in LDD, and don't even have LDD installed anymore, so I can't look at it. One possibility is that LDD was always "broken" in that regard, and more-or-less worked "by accident".

Although I remember someone else complaining that the meaning seemed to have changed, and at one point "FOOT" meant US Survey Foot, then all of a sudden "FOOT" meant International Foot. Although that could be wrong, or confused with something else...

I know that Autodesk is not consistent on this point. For example, when defining a coordinate system, the units will be US Survey Feet if you select "Foot". You have to go further down the list, and find "International Foot" for IF. That's backwards from the FBK, where FOOT = International and USFOOT = US Survey.