Accuracy comparison test - RTK vs GCPs

I recently did some testing of the accuracy of the export data of photogrammetry when using images tagged with RTK metadata compared to those constrained by GCPs and the combination of the two. I also looked at how the density of GCPs affected accuracy.

I found RTK only missions were capable of achieving the same accuracy as those fully constrained by GCPs.

And for my 100 acre test site, 10 GCPs were required to reduce vertical accuracy down to expected levels. However only 4 were required for horizontal accuracy convergence. 

Please feel free to share your thoughts