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cHECK eLEVATIONS

I have flown a quarry site and measure GCP's with high GPS (1cm accuracy).I have adjusted my model to the GCP's. After measuring the distances on MME, I find a diff of anywhere btwn 0.05cm on shorter legs and 0.15-0.20cm on longer legs.( I think some of the difference is the lack of projection). Some of the GCP's are approx 20m diff in elevation. So here's my question, How can I call out the elevation on MME to check my model?  Right click gives me the coordinates, but is there a way to get elevations. Even a cross section could give me the difference in elevation. I'm not concerned about the ASL/MSL elevation, I can adjust that to my job, I just want reassurance of the relative elevation differences.

 

Jamie Flewelling

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The shape of the model does not change when doing the manual realignment. If you care about the accuracy of your elevations you need to use lots of overlap and use Map Pilot's Active Connect mode to get the best model possible. You want your entire overlap report to be blue. Also when a large section of the survey area is water you will want to include a larger area around the top to provide more context. 

From there, the GCPs will apply a linear offset based on the differences between the generated DEM and the surveyed points.  

You can check your GCPs vs the model in the DEM file using GIS software such as QGIS. 

Zane
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