Somebody please show me what I am missing here:
I am experimenting with labeling in Carlson. Specifically I have some OR State plane south coordinates collected by GPS. I have the scale factor and the elevation factors for all the points. I wanted to test how Carlson Survey 2015 OEM calculates and labels the "2nd distance". For this case I will just refer to one line.
Here are my drawing settings: 
I have the correct distance units and i used an average ellipsoid height for the project of 5850. I then selected the "Grd>Gnd" option which is supposed to yield a ground distance on a line by line basis using the endpoints of the line selected. See the "ground" distance labeled in the image above.
Here are my coordinates:
1005 East. 5162641.465
Nrth. 178120.478
Elev. 5921.463 ortho
SF 1.000051 EF 0.99972007
1006 East. 5165181.402
Nrth. 178144.502
Elev. 5894.406 ortho
SF 1.000051 EF 0.99972136
I calculate in excel and get the following:
Ground distance = grid distance * 1/(average combined scale factor) = 2540.05 * 1/(0.9997717) = 2540.63
What am I missing (or doing incorrectly) here?
Thanks in advance.
Kevin,
Try setting the Report Distance Scale Factor . Also, you may need to set your base Z back to zero.
I keyed in your coordinates into Carlson 2013 and below are my results.
Here's a 3 minute YouTube video by Mr. Mark Silver on the subject.
Carlson Software: Dimension Grid and Ground, Automatically
As far as having Carlson automatically compute and apply a scale factor for points 1004-1005 and then a different one for 1005-1006, I don't know. If you figure it out please let us know.
Corey
Thanks for the reply.
I was hoping that the "Grd>Gnd" option would actually yield a ground distance computed from the average combined scale factor from endpoint to endpoint on each line as described in the user documentation.
I don't want to use an overall project scale factor. The "Grd>Gnd" option is represented as being a rigorous line by line reduction.
I will reach out to Carlson Software and see what information they can supply.
This is a screen capture from the Carlson help menu.
I heard back from Carlson tech support. The line needs to be drawn at elevation (read 3d Polyline) for the correct ground distance to be calculated.
I don't know if the software is using the NAD83 selection in the drawing setup to derive an ellipsoid height or if it is just calculating an elevation factor from the z value of the endpoints of the line. One would have to verify.
The line needs to be drawn at elevation to return the correct ground distance. I would assume that the calculation will be done with ortho heights if that is the Z field in the data file. Technically the elevation factor should be coming from ellipsoid heights in NAD83 if I am not mistaken. I suppose one would have to test the difference between ell ht derived ground distances and ortho ht ground distance are significantly different on a project basis.
Kevin Samuel, post: 341034, member: 96 wrote: I heard back from Carlson tech support. The line needs to be drawn at elevation (read 3d Polyline) for the correct ground distance to be calculated.
I don't know if the software is using the NAD83 selection in the drawing setup to derive an ellipsoid height or if it is just calculating an elevation factor from the z value of the endpoints of the line. One would have to verify.
Thanks for the update. That's good to know.
Corey
Kevin Samuel, post: 341034, member: 96 wrote: I heard back from Carlson tech support. The line needs to be drawn at elevation (read 3d Polyline) for the correct ground distance to be calculated.
I don't know if the software is using the NAD83 selection in the drawing setup to derive an ellipsoid height or if it is just calculating an elevation factor from the z value of the endpoints of the line. One would have to verify.
So Carlson provides incorrect values if the line is 2d and the routine doesn't check for that? Sounds like bad programming to me. I would prefer it used the point database because lines can be drawn at all kind of bad elevations. Thanks for the heads up Kevin
rambleon, post: 341105, member: 2107 wrote: So Carlson provides incorrect values if the line is 2d and the routine doesn't check for that? Sounds like bad programming to me. I would prefer it used the point database because lines can be drawn at all kind of bad elevations. Thanks for the heads up Kevin
I am pretty sure you can label by picking the points not the linework. Try to annotate a bearing and distance between points.
One can also annotate by points and it is supposed to work correctly. I haven't tested that method yet.
