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GCP Error with Arbitrary Coordinate System

Hello Support,

We are having an issue that happen periodically when we are using an arbitrary coordinate system for GCPs.  We go through the initial processing (adding photos, adding GCPs, basic editor) but we get an error saying that our RMS is too high.  (see screenshot)

We have only got this error when we use an arbitrary coordinate system and it has only happened on a few of our flights.  When we reprocessed the same flight using the same workflow, we did not get this error. 

We are curious why the same flight would yield different results and if there are steps to prevent this error from occurring?


Hello Lamp,

What is the difference between the RMS error you get processing the same project at different times?

A small difference could be attributed to the different marking of the GCPs. Are all the other parameters stable?
Are you using the same processing options?
Could you please attach 2 quality reports indicating the difference to better understand the problem?



I have attached a screen shot of our test when we only process 3 GCPs. We got a RMS error of 0.  The second time we process with all 11 GCPs, our RMS was .029 m (which was a warning not an error). I do not have a screen shot of that report.  We are looking to understand why we are getting mixed results when processing and ways to avoid getting this error.  Processing options / workflow was the same for all three.