Lab 6

Intro

One of the main goals of this week's lab was to show how GCPs can affect the results of the data processing. A GCP or ground control point is a tool that is used to manually place reference points for later use in processing. Pix4D, the software used in the processing of this project, is able to be used to manually locate and realign GCPs to the appropriate locations. 

Process

Before one can get started with aligning GCPs, you must first get your point cloud created and work from there. Once the point load has been created you can see with the tool used to correct GCPs that most of the points do not align with the marked GCP locations in the images. To correct this, we go into this tool and manual search for the marked locations that the GCPs where located. for this location, the GCPs were marked with orange arrows. After correcting the GCPs, you need to rematch and reoptimize the images. This is an automatic process you can start by clicking the rematch and reoptimize tool.

Final

In the finished map included in this post shows the physical markings on the ground where the GCPs were marked. With Pix4Ds GCP tool, it is easier to get accurate results and correct errors. Without correcting these errors, there will be inaccuracies that could possibly lead to incorrect data. It is also important to mark where the GCPs locations are taken so that they can be aligned in processing.