• Best practice and settings when running a photogrammetry project with drone photos including basic GPS data and survey grade GCP:s?

    I've been searching the forum and read all the manuals avalible for Context Capture Master and the process of aerotriangulation and productions of orthophotos. But I'm still uncertain on how the process should be conducted in order to achive best result…
  • Recommended number of control points - control point density

    I'm desperately searching for a page I've recently seen on the forum (or was it the Wiki?), describing the maths and process on how to determine a good distance between GCP;s on a large land survey project. - Is there anyone out there who know what…
  • Surveyed Ground Control measurements and there reuse with a different SRS

    For our ContextCapture projects we have two customers. One customer needs Nad83(2011) NCSP NAVD88 Geoid 18 (xyz units us survey foot), the other customer needs Local Space Rectangular. The difference between the two SRS's is normally a scale factor. Knowing…
  • What size do April Tags need to be?

    I created a project. I went to Tools and saw that April tags need to be at least 35x35 pixels. If I am flying a job with a Phantom 4 RTK at an altitude of 71m AGL that gives me a GSD if 1.95 cm/px If we calculate that out to 35px by 35px that gives us…
  • Why does my focal length change for the same camera in different photogroup?

    I'm using Sony A7R II with 28mm lens and I'm curious why my focal length change slightly? it's a prime lens and manufacturer spec says it's 28mm and the aero-triangulation optimized the focal length in the range of 27.13mm - 27.20mm for different photogroups…
  • Why do I lose marked GCPs during AeroTriangulation?

    I've imported photos from a DJI Phantom 3 and performed an AT on them, it works OK except for a bit of radial distortion. I then bring in and mark my ground control and do another AT using the setting 'Use control points for adjustment', but after AT…
  • control point ContextCapture

    Hi! I'm testing the accuracy of the photogrammetry process. So I use GCP and check point (CP). When I use only GCP the aerial triangulation's error is not relevant and the result is good but when i use GCP and CP the CP's error is higher than GCP's…
  • Control Points - ContextCapture

    I need to introduce Control Points in ContextCapture. How I can import a list of coordinates X,Y,Z from .txt file?