I have an issue where a job was started using the P4RTK and then was finished using a P4P. When the client entered the data into ARCgis, the RTK tiles moved south by 10klm and the P4P tiles were accurate. All controlled by GCPs, so no problem there. Any suggestions as to why the RTK data is a problem. I would have expected an error of 50 cm before rectification during processing.
Maybe a bad base or NTRIP point. Was it manually entered, averaged or corrected from a service provider?
If it was an NTRIP/CORS how far away was it? What CRS’s are they supporting?
Can you verify that the RTK solution was fixed throughout the entire project?
You can expect up to a 1-meter residuals between standard GNSS and RTK. It seems to me that 10km has to be a bust in coordinates somewhere.
This mission was a Linear flight plan using Google Earth base map and Aeropoints GCP’s, using eight GCPs with two known points in each segment. The base station was within the map area. There is no CORS/NTRIP service used. We had fixed solution during the entire flights (2 segments per map). Attached is screen shot of the end result,
The maps using P4P are correctly located.
That looks an awful lot like a scale factor issue, but I’ve never seen a scale factor affect of map like that more than about 1000 feet. there has always been problems with linear processing, but once again I’ve never seen anything quite like this. Usually it’s just twisting and warping.
Is it possible to find a picture almost directly over a GCP that was taken with the RTK and compare the coordinates? I would expect around 5-6 minutes difference in longitude. do you have another way to verify the base coordinate that was used?
You can also load the images into geosetter to verify the positions. It will look a lot like the DroneDeploy upload points.
Any checkpoints? Can you please share the processing report and the CSV you used for GCP’s? I would be curious to bring it into Civil 3D.
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Thank you for your suggestions. I made a mistake in the ESPG format. Once I corrected that, all maps displayed correctly. Simple error, but lost focus at a critical moment in processing.
Thanks guys.
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