Sorry I misunderstood. When the coordinate system is in US sruvey feet, you see the symbol ftUS , otherwise you see ft for international feet.
To clarify the situation, there are three coordinate systems:
- For the images: Written in the EXIF and automatically set by the software.
- For the GCPs: Set by the user according to the GPS measurement device used on the field.
- For the outputs: Set by the user depending on his needs.
By default the output coordinate system is:
- The same as the one of the images without GCPs.
- The same as the one of the GCPs if GCPs are included into the project.
However, the three coordinate systems can be different, meaning another output coordinate system can be selected independently from the geolocation reference of the images and the GCPs.
How to change coordinate system options: https://support.pix4d.com/hc/en-us/articles/202560029. To edit the vertical datum settings, check the box Advanced.
Regarding coordinate systems I also recommend this website that I find very helpful: http://spatialreference.org/.
Hope it answers your questions. If it remains unclear, please send me the quality report of the project (…\project_name\1_initial\report\project_name_report.pdf).