Im working on a thesis project for my bachelors in Geomatics where I compare the accuracy and suitability of UAV surveying vs traditional methods. Im using a phantom 4 pro and Nikon D5300 with a 35mm prime lens
I took over 900 images on my 26 acre site. 300+ nadir images, 300+ in a oblique grid pattern, 150 in a oblique circular pattern and around 100 with a ground based dslr (at face level and elevated 3m on a painters pole).
My first chunk (nadir images) processed very nicely. I had 11 GCPs, I used 2 as check shots. Everything is in a local coordinates system (UTM10 but without the scale factor as my GCPs were shot in with a total station). 333/334 images aligned, control point error = 0.003m Check point error = 0.028m
I used this for my DEM and Orthophoto as it has been my experience I get a better ortho from nadir images only.
My second chunk (oblique grid, circular photos and terrestrial photos) initially wouldn't align well with reference mode due to the fact my circular photos had bad elevation metadata. So I aligned using the disabled option and 611/632 images aligned which I was happy with. Everything looked good when I turned the camera positions on. I built a dense cloud with mild filtering and was very happy with the results so I proceeded to input my GCPs. When I was finished and optimized my alignment I now had huge (35m) GCP error and now when I view my cameras, it is a total mess. I dont believe I did anything different and now cant figure out what my next step should be to find the issue.
I am using this methodology and settings (
http://www.agisoft.com/index.php?id=31)
Any suggestions on where to start would be greatly appreciated.