I post processed one of my maps with 6 ground control points, when it was done, the ground markers all line up on the map preview on Maps Made Easy, but when I pull the geotiff into ArcGIS Pro, it is off 0.68 m to the east and south on all 6 markers. Now I can manually move these in GIS, but when I try to do it the DEM geotiff it changes the model and the hillshade becomes useless and so I am trying to figure out why my GCPs match on your map and Preview but are off on mine.
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The GCPs will line up with whatever you provide. The process takes your measured GCPs and allows you to move them line up with the Maps Made Easy created source layer. Then those points are moved to line up with the original GCP location.
Where did you get your GCPs?
It is off by .68 meters according to what as a reference?
Do the GCPs line up with that reference?
How they look come in ArcGIS Pro, with the coord system set to WGS 84(x,y) NAVD 88(z)
Shot in with a trimble on the RTKnet for the GCPs
That is just my measuring in ArcGIS Pro, its is but if I measure straight to the marker, is is 0.93 m at 315 degrees on all 6
Are you opening the newly created file and not the original?
Yes, it is the one with yesterday's date
It looks like the displacement you got between the original and GCP corrected version was primarily in the Latitude. The GCPs you provided have very little variation in longitude (only roughly .000005 degrees or so) but in latitude the difference was 8X that (.000040) which would explain what you are seeing. It seems your longitude degrees are off in your GCPs.
So what should I do to not have this happen again? I had to convert our the coordinates from the trimble to Lat Longs, as we are technically working in NAD 83 UTM Zone 15, but I had to convert to use the Maps Made Easy, but that is how all the data is being collected.
We can't really help you with your conversions. How you get your GCP data is beyond the scope of our support.
The realignment process will put it where you tell it to go.
Maybe open the original image with your surveyed points in your coordinate plane and get the GCPs that way.
Thanks
