The results for the sampled points on the surface were (negative numbers are a high stakeout, positive numbers a low stakeout - fill required)
I guess with a 0.25m contour gap the maximum possible error approaches 25cm.
The surface file was only 3.5Mb or thereabouts, so I guess I could make much closer contours and see if the differences in elevation remain as large.
I’d be interested in views about these results.
What this exercise reinforced for me is the need to be able to produce a surface stakeout report in Emlid Flow just the same as you can for point stakeout. It’s a pain taking points back into QGIS to produce the same result.
And for completeness, here’s the result from 102 staked points on a surface created from 1cm contours and with the same parameters as the last set of points. Given this is drone data those contours are inside the GSD…
The differences between this and the 25cm contours seem to be negligible.
I’m sorry for the radio silence. Thanks for the detailed explanation of your workflow and for sharing the results!
What this exercise reinforced for me is the need to be able to produce a surface stakeout report in Emlid Flow just the same as you can for point stakeout.
This is indeed a good feature to have when staking out surfaces. I’ll add this request to our internal list. Thank you for pointing that out!
I am discussing your case with the developers. Could you please share the DEM, TIN, and CSV used for this test? We want to reproduce the issue. Thanks!
Sampled the DEM with those points to generate the elevations for those points in the DEM
Could you please tell me what you mean by “Sampled the DEM”? Did you apply interpolation on the DEM or extract the values from the nearest pixel?
Hello @ruth.bongon I will send you the various documents by email to support or via and emailed link.
As for sampling QGIS allows to upload a series of points in a CSV and to then use those points to sample the Elevation at the nearest pixel in a chosen layer.
